it puts out 500 watts at 4 ohms. bridging is basically just combining 2 channels into 1 which is what the 1 is for. Alot of 2-channel amp put out 250 x 2 x 2, and then if your amp is bridgedable it puts out 500 x 1 (channel) @ 4 ohms. The bridging terminals are marked on the amplifier.