The ACC1000 is the clamp mount that comes with the BCC2000 bundle. The ACC1000P is exactly the same as ACC1000, but also comes with an Extension Pole that increases the clamping distance from 3.5 to 10.6 in (90 to 270 mm).
Yes, the clamp comes with two grip sides. One grip side is for clamping onto flat surfaces and another for poles and other curved surfaces. When installing your mount pick the most suitable grip side, flat or curved, for your environment.