Switch S1 is the power switch. Resistor R1 and light-emitting diode are used for power indication. The sensor MQ-3 needs to be heated to a certain temperature when working, so a heating wire is installed inside it.
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Professional PH Chlorine Meter CL2 Measuring Water Monitor with Probe for Swimming Pool Spa Water Quality Testing Device
Aliexpress UK
Compact and Portable: With its lightweight and compact design, this breathalyzer easily fits into pockets or handbags, making it a convenient accessory for on-the-go testing at social events or gatherings.
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2 in 1 PH Chlorine Meter Chlorine Tester PH Tester Chlorine Water Quality Testing Device CL2 Measuring Pool Swimming Accessories
Aliexpress UK
Convenient Design: The user-friendly breathalyzer features a straightforward interface, enabling quick and easy testing with results displayed clearly on the LCD screen. Versatile Use: Ideal for various situations, this device can be utilized at family gatherings or social events to monitor alcohol levels, promoting safety and compliance with regulations.
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DUSTY TC-24 Type-C Cable Tester Supports Type-C/USB Interfaces for Apple Android Devices Type-C/USB Interface Cable Testing Tool
Aliexpress UK
LCD Screen Display: The alcohol tester features a clear LCD screen that presents the breath alcohol concentration readings, making it easy to read and interpret results at a glance. Alcohol Test Range: 0-0.19% BAC.
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100pcs Urine Routine Test Strips Ph Testing Strips Testing Kit Medical Ketone Test Strips Protein Testing Strips Ph Test Strips
Aliexpress UK
Sturdy and : Made of high-quality alloy material, our alcohol breathalyzer is and will. Outdoor peace of mind: Our alcohol breathalyzer is a must-have for anyone who wants to avoid drunk driving.
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For Mold Testing Kit Home DIY For Mold Testing HVAC System Kit Detector For MOLD Testing Kit Test Measurement Inspection
Aliexpress UK
【User Friendly】: Insert the mouthpiece, and press the power button to start. The Alcohol Breathalyzer preheats in 10 seconds, then prompts you to blow for 5 seconds to display your result. It automatically powers off after 15 seconds of inactivity.
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USB Voltmeter, Ammeter, Power Capacity, Mobile Power Supply Testing and Testing Instrument, Battery Capacity Testing Instrument
Aliexpress UK
Compact and Portable: With its lightweight and compact design, this breathalyzer easily fits into pockets or handbags, making it a convenient accessory for on-the-go testing at social events or gatherings.
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Gold Testing Kit Gold Testing Stone Jewelry Tool 10K 14K 18K 22K Acid Tester Kit with Acid Gold Detecting Equipment Gold Testers
Aliexpress UK
Safety Precautions: Designed with safety in mind, the device includes warnings against using chemicals for cleaning and advises against exposure to contaminants, longevity and consistent for performance.
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Professional Scoliosis Testing Meter Metal Ball Level Spine scoliometer Measuring Tool for Hospital 0‑30° Testing Range
Aliexpress UK