ULN2003 Driver Board: A, B, C, D four-phase LED indicates the status of the stepper motor work | Stepper motor with a standard interface, when used directly pluggable | 5 line 4 phase can be used for ordinary ULN2003 chip driver, connect to the 2 phase , support the development board, with convenient use, direct docking | Compatible with ArduinoIDE UNOR3 MEGA 2560 1280 DSP ARM PIC AVR STM32 Raspberry Pi | 6 Sets Stepper Motor 28BYJ-48 ULN2003 5V Stepper Motor + ULN2003 Driver Board

2.4GHz Dual Mode WiFi + Bluetooth Development Board | Support LWIP protocol, Freertos | SupportThree Modes: AP, STA, and AP+STA | Ultra-Low power consumption, Compatible with Arduino IDE | ESP32 is a safe, reliable, and scalable to a variety of applications

TYPE-C USB D1 mini, it is a mini NodeMcu Lua WiFi board based on ESP-8266EX. | WIFI development board: on-board 5V 1A switching power supply, 4M bytes | this board contains 11 digital input and output pins, all pins have interrupt, PWN, I2C, 1-wire (except D0) and a micro USB connection; 1 input (under 3.2V), which compatible with Arduino; 500mA resettable fuse | WIFI development board,4M bytes.5V 1A switching power supply (switching power supply）onboard. | 6PCS ESP8266 ESP-12F D1 Mini TYPE-C USB Module Mini NodeMcu Lua 4M Bytes WLAN WiFi Internet Development Board for Arduino Compatible with WeMos D1 Mini NodeMcu

ESP32 is a safe, reliable, and scalable to a variety of applications | ESP32 development board support lua program, easy to develop, support LWIP protocol, Freertos, three modes : AP, STA and AP + STA. | Integrated 520-kBSRAM, 448-kBROM16-kBSRAMinRTC | USB driver chip: CH340C, with good system compatibility, higher download speed, and more stability. | you will get 2PCS PCS ESP32 Development Board TYPE-C USB CP2102 WiFi+Bluetooth Ultra-Low Power Consumption Dual Core ESP32-DevKitC-32 ESP-WROOM and 2PCS ESP32-DevKitC-32 ESP-WROOM-32 Expansion Board

Clock chip: high-precision clock chip DS3231SN; The DS3231 is an RTC IC developed by Maxim Integrated. It is a low cost, extremely accurate RTC IC with communication over I2C Interface. An interesting feature of DS3231 RTC IC is that it has integrated crystal oscillator and temperature sensor and hence you don’t have to connect an external crystal. | It is a low-cost, extremely accurate I2C real-time clock (RTC), with an integrated temperature-compensated crystal oscillator (TCXO) and crystal. | AITRIP 3PCS DS3231 Real Time Clock Module RTC Sensor High Precision AT24C32 IIC Timer Alarm Clock for Arduino Raspberry Pi | The DS3231 is an RTC IC developed by Maxim Integrated. It is a low cost, extremely accurate RTC IC with communication over I2C Interface. An interesting feature of DS3231 RTC IC is that it has integrated crystal oscillator and temperature sensor and hence you don’t have to connect an external crystal. | A precision temperature-compensated voltage reference and comparator circuit monitors the status of VCC to detect power failures, provide a reset output. In addition, RST pin is monitored as generating a μP reset. | The DS3231 is available in commercial and industrial temperature ranges, using a 16-pin 300mil SO package.

working voltage 3.6V to 6V | With LED indicator light, use 150mA and 3.3V regulation chip. With VCC、GND、TXD、RXD foot for the Bluetooth | Small size, low power consumption,high sensitivity for send and receive. | It's HC-06 Bluetooth module; Allows your device to both send or receive the TTL data via Bluetooth technology without connecting a serial cable to your computer. | used for short-range data wireless transmission,such as Bluetooth wireless data transmission,Industrial remote control, telemetry,Traffic, underground positioning, alarm,Smart home ect.

Pins Definition: DTR,RXD,TX,VCC,CTS,GND;RXD/TXD transceiver communication indicator | USB power has over current protection, using 500MA self-restore fuse. | Support Win95/98/98se/ME/2000/XP/win7 32bit 64bit /Vsita/, do not Support Win8 | Support Voltage:3.3V,5V | Package Content: 4pcs FT232RL USB To TTL Adapter

2.4GHz Dual Mode WiFi + Bluetooth Development Board | Support LWIP protocol, Freertos;ESP32 is a safe, reliable, and scalable to a variety of applications | SupportThree Modes: AP, STA, and AP+STA | Ultra-Low power consumption, Compatible with Arduino IDE | 1PCS 30Pin ESP32 Development Board 2.4GHz WiFi Dual Cores Microcontroller Integrated with Antenna RF Low Noise Amplifiers Filters

2.4GHz Dual Mode WiFi + Bluetooth Development Board | Support LWIP protocol, Freertos | SupportThree Modes: AP, STA, and AP+STA | Ultra-Low power consumption, Compatible with Arduino IDE | ESP32 is a safe, reliable, and scalable to a variety of applications

Test ranges:Inductors, capacitors , diodes, dual diode , mos, transistor, SCR , the regulator, LED tube, ESR, Resistance, Adjustable potentiometer | Can detect the transistor, MOSFET protection diode amplification coefficient and the base to determine the emitter transistor forward biased voltage. | High test speed, valid component test: 2 seconds (except in the larger capacitor of large capacitance measurement also takes a long time, the measured time of one minute is normal) | 128*64 big Backlight LCD display,only 2mA when stand by. | Auto power off function to avoid unnecessary waste, saving battery power, improved battery life