This Y shape Bow stop is made from Durable thermal plasticized rubber (TPR). TPR is a strong, flexible, reusable, weather resistant and recyclable injection molded material that performs like natural rubber. TPR will not leave black marks, on your boat like black natural rubber. The stop acts as a bumper to keep your boat from hitting your trailer when loading the boat from the water It has the following dimensions:5-3/4" span across and has 3' x 3' mount for a secure fit.