Finally! A reasonably priced tool for safely working on tube amps without a speaker. This small durable tool simply plugs into the output jack instead of a speaker. Toggle allows user to switch between 8 or 16 ohm applications. Rated at 50 watts, but should not be used on amps greater than 30 watts.These devices are designed for testing of amps on the bench for short periods of time.

( Thanks to Terry at Dlab for the inspiration)