PU Foam Silicone Insole M This is a PU (polyurethane) foam and silicone insole with excellent shock absorption and breathability. The main body is made of PU (polyurethane) foam, which is flexible and abrasion-resistant. It is soft yet elastic, providing high cushioning to protect your feet from shock. Multiple ventilation holes are placed to prevent foot stuffiness. On the foot side, the heel area offers excellent hold, and the toe area has a textured surface to prevent slipping. On the shoe side, silicone is placed in two locations to prevent slipping and shifting. The size can be adjusted by cutting between 23.0 cm and 25.5 cm. Size: 25.5 cm x 9.0 cm