Synergel Dimensions Gel Cushions use a medical grade silicone gel designed with a three dimensional layout that helps provide ventilation and protection from skin shear and friction while providing a high level of cushioning. The gel used in Synergel Dimensions Gel Cushions remains pliable and soft in extreme temperatures and is water insoluble. This proprietary silicone polymer was designed to mimic the same physical characteristics as human fat tissue. These characteristics make it ideal for use in places where the pad might get wet, like wheelchair seat cushions. Silicone gel won’t rot or dry out, will not flow or leak if cut or punctured. It is specifically designed to reduce pressure, impact, and vibration and provide protection from shearing and friction. Unlike other gel pads, these cushions will not retain heat and are odorless. Synergel Dimensions Gel Cushions are very durable and made in USA.Synergel Dimensions Gel Cushions Features:Cell design allows air flow.Helps prevent pressure sores.Does not retain heat.Odorless. Synergel Dimensions Gel Cushions Specifications:Sizes: 14 x 14, 16 x 16 and 18 x 18 inches.Thickness: 1/2 inch.Material: medical grade silicone.Made: in USA.