TMD's Chain Lock is a keyless bike lock that combines a Bluetooth proximity sensor and motion alarm with a hardened steel chain. The lock is shareable with friends and family and can withstand shock, rain, dust, and extreme temperatures. However, its high price of $280 may be a deterrent for many cyclists. The lock has earned an ART-2 certification and features an integrated motion alarm, but its battery life may be shorter than expected.
The TMD Chain Lock is convenient for those who lock their bikes multiple times a day, and its digital key can be shared with others. However, its high price is a significant drawback, especially when compared to equivalent analog bike locks that cost a quarter of the price.
The lock's battery life is expected to last up to nine months, but in testing, it dropped 16 percent after a week. The lock can be charged quickly, but it requires a proprietary cable.
