Pro Grip Superbike 724 Duo Density Road Grips (120mm) (Black/Green) ProGrip is the first company that offered the duo compound handgrip. These grips are made by two different density rubber materials. This is what riders are looking for: hard material in the inner part of the grip to fix better on the bar without any problem of slippery and soft material for reduction of all vibrations that the motorcycle can transmit. Comfort and technology for your hands. Harder density against the bar to keep the grip from slipping and soft-gel density where needed.