Having a spare key is always a good idea... That's why TEMO offers a magnetic key with lanyard for your TEMO 450 in case you misplace your original one or just want to have a spare on your keyring. The lanyard makes it safer to use when you're on the water and helps the key float if dropped in the water. This key includes a magnet that fits directly onto the TEMO 450 for switching it on. This functions as a key and kill switch/safety lanyard.