MQ-7 Gas Sensor Module The MQ-7 gas sensor module is a device that can detect the presence of carbon monoxide (CO) gas in the air. It is commonly used in applications such as gas leak detectors, safety devices, and industrial control systems. The MQ-7 sensor operates by using a chemical reaction between the CO gas and a conductive metal oxide to produce a current. The magnitude of the current is proportional to the concentration of CO gas in the air. The gas sensor can be used to detect CO gas concentrations in the range of 20-2000 ppm. It is important to note that CO is a poisonous gas that can be dangerous at high concentrations. It is recommended to use the MQ-7 sensor with caution and to take appropriate safety measures when working with it. This module provides both digital and analog outputs. The threshold level for digital output can be easily adjusted using the preset on the board. The MQ-7 sensor module can be easily interfaced with microcontrollers, Arduino and etc. Read our blog MQ sensor where we explained what is a gas sensor, what is 1ppm equal to, MQ sensor list of different series and their features. Applications: Domestic gas leakage detector Industrial CO detector Portable gas detector Standard Test Conditions of MQ7 Gas Sensor Temperature: 20°C ± 2°C Humidity: 65% ± 5% RH Standard Test Circuit: Vc: 5.0V ± 0.1V; Vh(high):5.0V±0.1V Vh(low): 1.5V±0.1V

MQ-8 Gas Sensor Module The MQ-8 gas sensor module is a device that can detect the presence of hydrogen gas in the air. It is commonly used in applications such as gas leak detectors, safety devices, and industrial control systems. The MQ-8 sensor operates by using a chemical reaction between the hydrogen gas and a conductive metal oxide to produce a current. The magnitude of the current is proportional to the concentration of hydrogen gas in the air. The sensor can be used to detect hydrogen gas concentrations in the range of 100-10000 ppm. Using a simple circuit to convert the change in conductivity of the gas concentration corresponding to the output signal. MQ-8 hydrogen gas sensor of high sensitivity, the monitoring of the other hydrogen-containing gas is also very satisfactory. This sensor can detect a wide range of hydrogen gas, city gas, in particular, is a low-cost sensor for a variety of applications. Suitable for home or industrial hydrogen leakage monitoring devices. Can not interfere with ethanol vapor, soot, carbon monoxide, and other gases. Applications: Detect leakages in the industry Used in mines Can be used in refrigerators and AC

MQ-9 Gas Sensor Module This is MQ-9 Carbon Monoxide, Methane, and LPG Gas Sensor Module can be used to sense Carbon Monoxide and Methane Gas. The sensitive material of the MQ-9 gas sensor is SnO2, which with lower conductivity in clean air. It makes detection by the method of cycle high and low temperature, and detect CO when the low temperature (heated by 1.5V). The sensor’s conductivity is higher along with the gas concentration rising. The MQ9 Gas Sensor Module conductivity is higher along with the gas concentration rising. When temperature rises (heated by 5.0V), it detects Methane, Propane, combustible gas, etc. and cleans the other gases as it absorbed under low temperature. MQ-9 usually applied in domestic gas leakage detector, industrial gas detector, portable gas detector, etc. When the high temperature (heated by 5.0V), it detects Methane, Propane, etc. combustible gas and cleans the other gases adsorbed under low temperature. Read our blog MQ sensor where we explained what is a gas sensor, what is 1ppm equal to, MQ sensor list of different series and their features. MQ9 Gas Sensor Wire Connections: VCC - Positive pole (5V) GND - Negative pole DO - TTL switch signal output AO - Analog signal output Applications: The domestic gas leakage detector Industrial gas detector Portable gas detector

MQ131 Ozone Gas Detection Module The MQ131 gas sensor module is a device that can detect the presence of ozone gas (O3) in the air. It is commonly used in applications such as air quality monitors and industrial control systems. The MQ131 sensor operates by using a chemical reaction between the ozone gas and a conductive metal oxide to produce a current. The magnitude of the current is proportional to the concentration of ozone gas in the air. The sensor can be used to detect ozone gas concentrations in the range of 0.05-10 ppm. Ozone is a toxic gas that can be harmful to humans at high concentrations. It is recommended to use the MQ131 sensor with caution and to take appropriate safety measures when working with it. The sensitive material of the MQ131 gas sensor is O3 SnO2, which with lower conductivity in clean air. When Ozone gas exists. The sensor’s conductivity is higher along with the gas concentration rising. Please use a simple electro circuit, Convert the change of conductivity to corresponding output signal of gas concentration. MQ131 gas sensor has a high sensitivity to Ozone, also sensitive to O3 CL2, NO2, etc. Features: Detection Gas: Ozone (O3). Detection Range: 10 to 1000 ppb (parts per billion). Sensor Type: Semiconductor. Operating Voltage: Typically 5V DC. Output: Analog signal output, with a voltage range of 0-5V. Sensitivity: High sensitivity to ozone and other strong oxidizing gases like chlorine (Cl2) and nitrogen dioxide (NO2). Response Time: Fast response and recovery. Durability: Long service life and reliable stability. Interface: Easy to interface with microcontrollers like Arduino and Raspberry Pi. Power Consumption: Low power consumption, suitable for continuous monitoring APPLICATIONS: Domestic ozone concentration alarm Industrial ozone concentration alarm Portable ozone concentration detector

MT8870 DTMF Voice Decoding Module The DTMF Decoder Module is the ultimate solution for projects requiring dual-tone multi-frequency decoding. Ideal for modem interfaces, mobile radios, and other DTMF applications, this module offers versatile compatibility and user-friendly design. With onboard LEDs, low power consumption, and adjustable guard time, it ensures quality performance and easy integration into UNO/MEGA2560/DUE boards. The central office quality and internal gain-setting amplifier guarantee optimal signal reception, making it a reliable choice for diverse projects. Convenient input interfaces, multi-channel outputs, and complete functionality make this module a must-have for enthusiasts and professionals alike. Purchase now and experience seamless DTMF decoding! Features: Onboard voice input interface Low power consumption Internal gain setting amplifier Onboard LED, it is very convenient to check the output state. Adjustable guard time Central office quality Onboard 3.5mm input interface 5 Channel interface On-board MT8870 frequency decoder chip Power-down mode Inhibit mode Onboard audio input interface Onboard LED lights for output state indicationComplete DTMF Receiver. Does not require external circuits or wiring, it can be inserted directly into the UNO/MEGA2560/DUE board to use. 12-Digital outputs decode mobile and fixed telephone keys (0-9, * #). Also, another 4 Digital outputs (ABCD) can use “DTMF Dial” for Software control. MT8870 DTMF Decoder Circuit Diagram: Applications: Modems, mobile radios, call routing. Mobile-controlled robots. Home Automation. Menu navigation via phone keypad. Industrial Automation. Education. Prototyping MT8870 DTMF Decoder Module - Arduino Test with PWM Audio Synth Tones

MTQ911 Temperature controlled variable soldering iron combination set The MetroQ Temperature-controlled variable soldering iron combination set MTQ 911 is a complete soldering kit that includes everything you need to get started soldering. The set includes a variable soldering iron, a dust-blowing ball, a soldering wire, a desoldering wire, a soldering iron stand, a rosin, a brush, two screwdrivers, a triangle plate, and a lever. All of the items are stored in an attractive plastic container. The variable soldering iron has a temperature range of 200-450 degrees Celsius, so you can easily set it to the correct temperature for the task at hand. The dust-blowing ball helps to keep the soldering iron tip clean, while the soldering wire and desoldering wire are essential for making and breaking solder joints. The soldering iron stand keeps the iron safe and secure when not in use. The rosin helps to improve the flow of solder, while the brush is used to clean the soldering iron tip. The two screwdrivers are for adjusting the soldering gun tip and the lever is used to release the soldering iron from the stand. The MetroQ temperature-controlled variable soldering iron combination set MTQ 911 is a great value for the price. It is a complete soldering kit that includes everything you need to get started soldering. The soldering gun set is well-made and durable, and it comes with a variety of useful accessories. Features: Variable soldering iron with temperature range of 200-450 degrees Celsius Dust blowing ball Soldering wire Desoldering wire Soldering iron stand Rosin Brush Two screwdrivers Triangle plate Lever Attractive plastic container The MetroQ Temperature controlled variable soldering iron combination set MTQ 911 is a great choice for anyone who needs a complete soldering kit. It is well-made, durable, and comes with a variety of useful accessories.

Multicolor Handheld Spot Welding Pen for 18650 Battery – Automatic Trigger DIY Welding Tool This handheld spot welding pen is designed to make 18650 battery welding quick, precise, and effortless. Built with a thick copper bar, it delivers strong conductivity and high working efficiency, ensuring consistent and reliable welds. Its integrated, compact design not only looks neat but also improves heat dissipation, helping the tool maintain stable performance during long sessions. The dual-spring structure allows each welding arm to move independently, making it easier to adjust and work comfortably. With a built-in limit switch, the pen enables true one-hand operation - no need for foot pedals or extra triggers. Whether you're assembling battery packs, repairing electronics, or building DIY power projects, this welding pen offers stable performance, long service life, and a smooth user experience. Features: Thick copper bar design improves efficiency and durability. Integrated body structure for better heat dissipation and neat appearance. Dual-spring mechanism allows each welding pen to move independently. Built-in limit switch enables one-hand automatic trigger operation. Comfortable to hold, stable during use, and suitable for extended work sessions. Ideal for welding 18650 batteries and other small electronic assemblies. Durable, wear-resistant construction designed for long service life.

Multifunction Delay Relay Switch Module 12 voltage relay switch, easy to use. With emergency stop function (“stop” button) and reverse polarity protection which can avoid burning by reverse connection.

Multifunctional DC 24V 1 Channel Relay Module Low Level The Multifunctional DC 24V 1 Channel Relay Module is designed to control various devices and loads. It uses a high-quality double-sided FR-4 circuit board for better performance and durability. The module has clear power and relay indicators, so you can easily see its operation. The relay can turn on when a low-level signal is input, making it simple to control other devices. It features both normally open and normally closed contacts, offering flexibility in your projects. The 24V relay module uses a blue KF301 terminal for easy wire connections.

Multitec 150B Wire Stripper & Cutter This Multitec 150B Wire Stripper & Cutter is a high grade stainless steell stripper/cutter ideal for professionals. The tool is suitable for the flush-cutting action. The Multitec Wire Cutter is mainly used to strip and cut the wire with a 12-24 gauge. The black oxide finish prevents corrosion. Based on the wire size, screws have to be adjusted. The Wire Stripper typically uses a combination of mechanical and blade-based stripping techniques to remove insulation from wires. The machine is equipped with adjustable blades that can be set to specific stripping lengths, allowing for efficient and precise stripping of a variety of wire sizes and types. check out : 68C Multitec Wire Stripper and Cutter Applications: Can be be used for professional use Industrial applications