A used 16 Ohm THD Hot Plate Attenuator in Excellent condition with modest wear and tear.

FROM THD ELECTRONICS:

The award-winning Hot Plate® is the world's most popular power attenuator. It lets you get your amp's full of distortion at any volume.  

Hot Plate colors are related to their impedances. There are five different Hot Plate models: The 2Ω (gold), the 2.7Ω (green), the 4Ω (red), the 8Ω (purple), and the 16Ω (blue). To optimize tone and function, the impedance should be the same on your amplifier, Hot Plate and speaker cabinet.