Specifications & Requirements
The TL-1 and TL-2 both plug into standard 15-amp, 120V wall sockets.
The TL-3 is also 120V, but requires a 20-amp circuit. This means that the wiring in the wall and the circuit breaker need to be setup for 20-amp. Some homes have this wiring already. The sauna comes with a 5-20P style plug and corresponding 5-20R receptacle for the outlet.
The TL-4 is only available in 220V, and has a 6-15P style plug. It also comes with its corresponding wall receptacle 6-15R or 6-20R.