It is a 5V 1 Channel Without optocoupler. The relay normally open interface maximum load: AC 250V/10A, DC 30V/10A. It has a trigger current of 5mA, and module working voltage of DC 5V. Each channel of the module can be triggered by a jumper to set a high level or a low level. Fault-tolerant design, even if the control line is disconnected, the relay will not move. With status indicator: power (green), 1-channel relay status indicator (red). All module size interfaces can be directly connected through the terminal block, which is convenient and practical.

This is a 2 Channel (Dual channel) isolated 5V 10A relay module Optocoupler for Arduino, PIC, ARM. It can be used to control various appliances and other types of equipment with a large current. It can be controlled directly with 3.3V or 5V logic signals from a microcontroller (Arduino, 8051, AVR, PIC, DSP, ARM, ARM, MSP430, TTL logic). This relay has a 1×4 (2.54mm pitch) pin header for connecting power (5V and 0V), and for controlling the 2 relays.

The ADXL335 is a small, thin, low power, a complete 3-axis accelerometer with signal conditioned voltage outputs. The ADXL335 Module 3-axis Analog Output Accelerometer measures acceleration with a minimum full-scale range of ±3 g.

This power supply module is based on the AMS1117 5V regulator. It is capable of regulating a wide range of input voltage (6.0 to 12V) down to a fixed 5V output at up to 1A  Standard 0.1″ header pins provide a means of connecting to its input and output terminals.

The DHT11 Humidity & Temperature Sensor Module is a basic, low-cost digital temperature and humidity sensor. It uses a capacitive humidity sensor and a thermistor to measure the surrounding air and outputs a digital signal on the data pin (no analogue input pins needed). Its very simple to use, and libraries and sample codes are available for Arduino and Raspberry Pi.

DS1302 is DALLAS company launched a trickle charge clock chip, containing a real-time clock/calendar and 31 bytes of static RAM, communicating through serial interface simple and single-chip microcomputer. The real-time clock/calendar circuit provides seconds, hours, days, weeks, months, years of information, a number of days in the month and leap year can automatically adjust. The clock operation instructions through the AM/PM decided to use 24 or 12-hour format.

It is LM2596 HV DC-DC Buck Converter with voltage rating 4.5-50V to 3-35V. This step-down power module is adjustable with a potentiometer.

The PAM8403 5V 2-Channel Stereo Audio Amplifier is a 3W+3W, class-D audio amplifier. Allowing it to achieve high-quality sound reproduction. The new filterless architecture allows the device to drive the speaker directly, requiring no low-pass output filters, thus saving system cost and PCB area. With the same numbers of external components, the efficiency of the PAM8403 is much better than that of Class-AB cousins.

This is PL2303 PL2303HX USB To TTL(Serial) Converter Module – 5 Pin. Adopt imported controller RS232 TTL, which can stabilize the flash with a high-speed 500mA self-recovery fuse for protection. Two data transmission indicator can monitor data transfer status in real-time. Reserve 3.3V and 5V pin interface, easy for DDWRT of different voltage system that needs power. The entire board is coated by a high quality transparent heat-shrinkable sleeve, making the PCB in insulation state from outside, so that the board won’t be burnt down by a material shortcut.

This is tiny and compact digital voltmeter with a green LED Display. The  0.28inch 0-100V Three Wire DC Voltmeter Green Panel requires only a few minutes of configuration and is as simple as directly connecting wires to the source you want to measure.