Gaugemaster OMNI 21 & 8 Pin Decoder The DCC27 is a multi-use decoder which can be used with locomotives that have 8 Pin or 21 Pin sockets. HO Scale, OO Scale. KEY FEATURES: Smooth Operation 14/28 and 128 Speed Steps Plug and Play Transponder ID-equipped All Mode Programming Decoder Reset CV Motor Isolation Protection Advanced Consisting 2 and 4 Digit Addressing DCC Compatability Technical CURRENT RATING 1A (1.8A Peak) FUNCTIONS 4 NUMBER OF PINS (DECODER) 21 NUMBER OF PINS (HARNESS) 8 Measurements: LENGTH 22mm WIDTH 16mm HEIGHT 5mm HARNESS LENGTH 75mm