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.