This version of our original Ribbed Ring has a smaller band cross section resulting in 33% material reduction - end result is a stretchier ring with a more gentle restriction. The original Ribbed Ring is still available – it is a customer favorite when it comes to donut style rings. The PFBlend in both rings stretch more than most TPR and Silicone rings of the same style. Made of PF Blend a proprietary blend of Silicone and TPR developed to provide superior stretch, comfort, and durability. Safe with water-based lubes wash thoroughly with mild soap and water. Not compatible with latex. Store separately.