Replacement (aftermarket) AC Power Adapter for the following Boss products: Loop Station RC-2, Compression Sustainer CS-2, & Compression Sustainer CS-3. These power supplies use a center negative pin as required by these products. Do not use positive center pin power supplies with these units! It will damage them. Specifications: I/P AC:100V~240VAC 50-60Hz O/P DC:9V DC 1A Chord: 43in Tip: (-)center, (+)outer