These are a light weight, low height, extruded EPDM rubber, contour chocks that are paired with black, 1/4 inch, braided nylon rope. Their low profile is designed for use with aircraft with wheel fairings or “pants”. Also suitable for smaller tires or carts. Its aggressive tire contact area promotes adhesion and friction. Material: EPDM Rubber Size: 2"H x 4"W x 3.5"LWeight: 3 lbs.