4 Cell 18650 Lithium ion Battery Holder This 18650 Lithium ion Battery Holder is a high-quality Lithium battery holder that can hold four 18650 Lithium batteries. It's a space-saving battery holder with built-in PCB protective circuits for securing rechargeable 18650 Lithium-Ion Cells with increased energy density and reduced weight. This Lithium ion Battery Holder is designed for 3.7-volt, high-energy, low-weight mobile electronics, industrial, and telecommunications applications that require circuit protection to prevent battery damage. Applications: Computer memory, power backup systems Digital readers Laptop and touchpad computers PLC and industrial controls

4 Channel (I2C or SPI) 3.3V-5V Bi-Directional Logic Level Converter If you've ever tried to connect a 3.3V device to a 5v system, you know what a challenge it can be. The bi-directional logic level converter is a small device that safely steps down 5v signals to 3.3V and steps up 3.3V to 5v at the same time. This level converter also works with 2.8V and 1.8V devices. What separates this logic level converter from our previous versions is that you can successfully set your high and low voltages and step up and down between them safely on the same channel. Each level converter has the capability of converting 4 pins on the high side to 4 pins on the low side with two inputs and two outputs provided for each side. The level converter is very easy to use. The board needs to be powered from the two voltage sources (high voltage and low voltage) that your system is using. High voltage (5v for example) to the 'hv' pin, low voltage (3.3V for example) to 'lv', and ground from the system to the 'gnd' pin logic level shifter bi-directional with 4 channels between high logic and low logic small module with 1.3Cm x 1.5Cm with 2 rows of 6 pin compatible with a breadboard, can be directly used in breadboard usage: for example, high voltage is 5v, low voltage is 3.3V hv connect with 5v power supply lv connect with 3.3V power supply and connect the power negative pole lvx input/output 3.3V TTL hvx input/output 5v ttl bi-directional transform between lvx and tvx Features: Mutual transform between 5V TTL and 3.3V TTL Four channels of logic and high voltage low voltage logic can two-way transform Portable and light, with 2 rows 6 pin contact pins Level Converter- 4 Channel Compatible with the bread plate, can be used directly put on the breadboard 4 Channel Module (great for I2C or SPI) and will work with all microcontrollers, Arduino, Raspberry Pi, Intel Edison, NXP Mbed Also check 2 Channel Logic Level Converter (I2C, UART, 5V-3.3V) available on the Iotcart website. It is a small device designed to safely step down 5V signals to 3.3V and simultaneously step up 3.3V to 5V. The converter is bi-directional and works with 2.8V and 1.8V devices as well. It has two inputs and two outputs for each side, allowing the conversion of 4 pins on the high side to 4 pins on the low side.

4 Channel 12V Relay Board This 4-channel 12 V relay module is a low pull, high release relay module and features energization status indicator light, release status led is off. By default, this is a 5V relay module and uses jd-vcc for the relay power and is compliant with international safety standards, control, and load areas isolation trenches. The 4 channel relay module can be used to control various appliances and other types of equipment with large currents. The maximum output of the relay module is AC250V 10A and DC5V 10A. The four-channel can be used to switch multiple loads at the same time since there are four relays on the same module. This is useful in creating a central hub from where multiple remote loads can be powered. It is useful for tasks like home automation where the module can be placed in the main switchboard and can be connected to loads in other parts of the house and can be controlled from a central location using a microcontroller. Note: If either of the relays does not turn on: The contacts might be welded due to overcurrent/arcing. Shaking the module firmly might help unstick the contacts The driver circuitry might have been damaged due to overvoltage. Input polarity might be incorrect. Jumper might not have been moved to the correct position Applications Switching mains loads Home automation Battery backup High current load switching read our blog explaining the relay applications , provides comprehensive information about relays, their working principles, construction, and various types.

4 Channel 5V Relay Board This 4 channel 5V relay module is a low-pull, high-release relay module and features an energisation status indicator light; the release status LED is off. By default, this is a 5V relay module that uses JD-VCC for the relay power and is compliant with international safety standards, control and load areas isolation trenches. The 4 Channel Relay Module is a convenient board that can be used to control high voltage, high current loads such as motors, solenoid valves, lamps and AC loads. It is designed to interface with microcontrollers such as Arduino, PIC, etc. The relay terminal (COM, NO and NC) is being brought out with a screw terminal. It also comes with an LED to indicate the status. The 4 channel relay module can be used to control various appliances and other types of equipment with a large current. The maximum output of the relay module is AC250V 10A and DC5V 10A. Applications: Switching mains loads Home automation Battery backup High current load switching Also check the 8 Channel 5V 10A Relay Module . Also, check our relay switch collection.

4 Channel Relay Wireless Module This is a 4 channel relay module which can be controlled by a wireless remote through a wireless RF link. The wireless board can operate within a range of 50m when the remote is in line of sight and around 25m when indoors. The RF link on this board works on the 433 MHz frequency. How to link the 4 channel relay with remote? To link the remote and relay, power relay board, hold down the button for about 1 second to learn to let go. Learn indicator light flashes, press the button on the remote control to learn indicator light flashes after a few off, both represent learning success. Features: Control: Allows wireless control of up to four separate electrical devices or appliances. Communication: Based on the ESP-12F module, which uses the ESP8266 chip for Wi-Fi connectivity. Voltage: Operates on a DC 12V power supply. Output: Each relay can handle loads up to 10A. Indicators: Includes LEDs for power and relay status indication. Mounting: Features mounting holes for easy installation. Modes: Supports two working modes - direct connection to a cellphone or connection via a router. Additional Function: The ESP-01 can work as a microcontroller when disconnected from the relay module. Applications: Home Automation: Control lights, fans, and other appliances remotely. Security Systems: Manage security devices like alarms and cameras wirelessly. Remote Monitoring: Monitor and control devices from a distance, ideal for industrial and agricultural applications. Smart Home Projects: Integrate with smart home systems for automated control. Robotics: Use in robotic projects to control multiple actuators or motors. IoT Projects: Suitable for Internet of Things applications, enabling remote device management. Wireless Control: Operate devices like garage doors, gates, and other remote-controlled systems.

4 Channel Solid State Relay 4-Channel Solid-State Relay is somewhat similar to that of a mechanical relay & the difference is that there is no moving contact in a Solid-State Relay. Here we make use of a Phototrriac coupler to turn it ON and OFF. It finds its application in AC circuits as a TRIAC has got only limited applications in DC. This module is ideally suited to controlling larger voltages with the project. This is a 4 channel relay module that can be used to activate up to 240V AC. This allows you to build in device control, operating lighting, or triggering systems when the module is triggered. With the labeled screw terminals it's easy to connect. Solid State Relay - Solid State Relay (SSR) has advantages such as more efficient switching speeds, more stable operation against electrical noise, longer service life, resistance to physical vibrations and resistance to moisture, which distinguish this type of relay from ordinary mechanical relays. These relays are preferred in places that require fast and precise operation such as computer peripherals, medical devices. Solid-state relays do have several advantages over mechanical relays. One such advantage is that they can be switched by a much lower voltage and at a much lower current than most mechanical relays. Also, because there are no moving contacts, solid-state relays can be switched much faster and for much longer periods without wearing out. This is a quad-channel relay module which can be used to activate up to four separate 240V AC. This allows you to build in device control, operating remote lights or triggering systems when the module is supplied the signal.The screw terminals are well labeled and definition of the units function is shown underneath. Also, read our blog on What is a Relay detailing how it works, relay contact types, and different types of relays and their application. Applications: Control outputs from programmable controllers and positioning controllers Office Automation, Home Automation

4 in 1 Heat sink Silver for Raspberry Pi 4B The Heat Sink Kit for Raspberry Pi 4B is your go-to solution for optimal cooling performance. This four-piece aluminum kit is designed for easy installation, making it accessible for users of all levels. Crafted with high-quality aluminum, our heat sinks guarantee durability and efficient heat dissipation. Choose the stylish silver finish to enhance the aesthetic appeal of your Raspberry Pi setup. Additionally, we offer anodized black for superior heat dissipation and gold with a copper main chip heat sink. Versatile compatibility ensures that our heat sink kit is suitable for Raspberry Pi 4B, providing a comprehensive cooling solution for your device. Made with precision and attention to detail, this heat sink kit is the ideal accessory to ensure your Raspberry Pi 4B operates at its best, even during demanding tasks. Upgrade your cooling solution with this Heat Sink Kit for Raspberry Pi 4B. Key Features: Optimal cooling performance. Durable high-quality aluminum construction. Easy installation for users of all levels. Compatible with Raspberry Pi 4B. Stylish silver finish. Precision craftsmanship. Comprehensive cooling solution.

4 pieces 10 X 2 Cm Gear Motor Robot Wheel & 4 pieces 200 RPM Gear Motor This set includes four 200RPM geared motors and 10x2 cm wheels, ideal for robotics and all-terrain applications. These Center Shaft DC Gear Motors offer reliable performance with a 12V 200 RPM output and are easy to control with an Arduino using an L298N H-bridge module. The motors have a 3mm threaded shaft for quick attachment to wheels or other assemblies, plus a sturdy metal or plastic gearbox for heavy-duty use in robotics and industrial projects. Check out: 200 RPM GEAR MOTOR+10X4 WHEEL - SET OF 4 Note: Depending upon the Manufacturer given dimensions may vary in the range of ±5%.

4 pieces 7 X 2 Cm Gear Motor Robot Wheel & 4 pieces 200 RPM Gear Motor These are 200RPM geared motor and 7 x 2 cm wheel ( 4 sets). The geared motors are simple DC Motors featuring gears for the shaft for obtaining the optimal performance characteristics. They are known as Center Shaft DC Geared Motors because their shaft extends through the center of their gearbox assembly. These standard size DC gear Motors are very easy to use. Also, you don’t have to spend a lot of money to control motors with an Arduino or compatible board . TheL298N H-bridge module with onboard voltage regulator motor driver can be used with this motor that has a voltage of between 5 and 35V DC. This DC Motor of 12V 200 RPM can be used in all-terrain robots and a variety of robotic applications. These motors have a 3 mm threaded drill hole in the middle of the shaft thus making it simple to connect it to the wheels or any other mechanical assembly. Nut and threads on the shaft to easily connect and internally threaded shaft for easily connecting it to the wheels. These DC Geared motors with robust metal/Plastic gearbox for heavy-duty applications, and ideally suited for robotics and industrial applications. The 7 x 2 cm wheels are high quality wheels, they are easy to mount and durable.

4 pieces 7 X 4 Cm Gear Motor Robot Wheel & 4 pieces 200 RPM Gear Motor for Robotics Science Project These are 200RPM geared motor and 7 x 4 cm wheel ( 4 sets). The geared motors are simple DC Motors featuring gears for the shaft for obtaining the optimal performance characteristics. They are known as Center Shaft DC Geared Motors because their shaft extends through the center of their gearbox assembly. These standard size DC gear Motors are very easy to use. Also, you don’t have to spend a lot of money to control motors with an Arduino or compatible board . TheL298N H-bridge module with onboard voltage regulator motor driver can be used with this motor that has a voltage of between 5 and 35V DC. This DC Motor of 12V 200 RPM can be used in all-terrain robots and a variety of robotic applications. These motors have a 3 mm threaded drill hole in the middle of the shaft thus making it simple to connect it to the wheels or any other mechanical assembly. Nut and threads on the shaft to easily connect and internally threaded shaft for easily connecting it to the wheels. These DC Geared motors with robust metal/Plastic gearbox for heavy-duty applications, and ideally suited for robotics and industrial applications. The 7 x 4 cm wheels are high quality wheels, they are easy to mount and durable.