I hooked it up to a 9v battery and used it as an auxiliary alarm for my little giant air con condensation pump. Works great, should last 10 years, that's how long it takes that 9 volt battery to go down to 3 volts. Keep in mind that this isn't as loud or uncomfortable as a fire alarm. Loud enough for me. Very good price. I tested them and they all worked. A very inexpensive solution for my small project notification system.
WETEN USB Rechargeable Self Defense Keychain Alarm For Women - Waterproof 130 DB Security Panic Button Siren Whistle With LED Light - Safety Sound Alert Device Key Chain In Black
14 Review
Rechargeable Personal Safety Alarm Keychain With Low Battery Notice And Strobe Light - Extra Loud Double Speakers - Pearly White (Vantamo)
14 Review
USB Rechargeable Waterproof 130 DB Security Panic Button Siren Whistle With LED Light Self Defense Personal Alarm Keychain For Women Safety Sound Alert Device Key Chain By WETEN (White)
16 Review
2 Pack 130 DB Rechargeable Self Defense Keychain Alarm - Emergency Personal Siren With LED Light For Women, Kids, Elderly & Joggers By WETEN (Black&White)
12 Review
Enhance Your Network Connection With Dingsun RJ45 Coupler - Compatible With Cat5, Cat5E, Cat6, And Cat7 Ethernet Cables (Black 10 Pcs)
35 Review
Fitbit Versa 3 Smartwatch Replacement Band: TOYOUTHS Elastic Nylon Fabric Strap For Women & Men
50 Review
🔋 TalentCell PB240A1 | 24V Lithium Ion Battery with 22400mAh Capacity | Rechargeable Power Pack for LED Light Strip, CCTV Camera, Smartphone & More
26 Review
Effortlessly Navigate Your Laptop Or Desktop With The Perixx PERIPAD-501 Wired USB Touchpad
27 Review