"The softness of Gel and the strength of duo density." RVGS: Reduced Vibration Gel System - all gel on the outside. Grey base against the bar (37 shore). Exterior in gel for soft, ergonomic fit (15 shore) - made from the same high-tech rubber compounds used in Formula One racing cars. Super soft and super durable with great adhesion. Patented process co-molds the RVGS in the grip. Gel molds to the hand as pressure is applied. Sold as a pair.