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10 in 1 Digital PH Meter Water Quality Tester PH/Cl₂/TDS/EC/Hardness Hydrogen-rich Detector for Drinking Water Aquariums Pools
Aliexpress UK
One is gone and one is broken. The expiration date is 1972!
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4 in 1 Aquarium PH Meter ORP H2 TEMP Hydrogen-rich Digital Tester Portable Pen Multi-function Water Quality Detector for Pool
Aliexpress UK
Tube No. 112SA. Tube Layout [ Detector Tube ]. CAS No. 74-90-8. Shelf Life 3 Years. Stain Color Brownish Red.
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2/3/4 in 1 PH ORP H2 Temperature Hydrogen-rich Meter Portable Pen Water Quality Purity Detector for Aquarium Pool Hydroponic
Aliexpress UK
This detector monitors four types of gases: LEL, oxygen, carbon monoxide, and hydrogen sulfide. It features a slim design that enhances portability and ease of use. Gas Types : LEL, Oxygen, Carbon Monoxide, Hydrogen Sulfide.
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Leak Detector Freon CFC HFC Halogen Gas Refrigerant Air Monitor Conditioning R22a R134a Gas Meter Automatic Refrigeration
Aliexpress UK
High precision portable CO, H2S, O2 and LEL gas tester with compact size and light weight, very easy to carry and operate. Detect 4 kinds of gas: carbon monoxide(CO), hydrogen sulfide(H2S), oxygen(O2) and combustible gas(LEL).2.
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Smart Natural Gas Alarm Sensor CO Carbon Monoxide Poisoning Smoke Gas Monitoring For Fire Security Detector APP Control For Home
Aliexpress UK
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Home Security Combustible Gas Leakage Sensor LPG Propane Butane Methane Natural Gas Detector CO Carbon Monoxide Alarm Fireproof
Aliexpress UK
(Excluded.).
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90-240VAC Kitchen CH4 Natural Gas Leaking Detector Magnetic Solenoid Valve Cut Off Coal Gas Fire Alarm Sensor For Home Security
Aliexpress UK
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Tuya Smart Zigbee Natural Gas Sensor Combustible Household LPG Gas Leakage Alarm Detector 70dB Sound APP Control Need Zigbee Hub
Aliexpress UK