Rubber tips are made of durable rubber, easy to install and wear resistant. Inner diameter is 12mm, height is 35mm, standard size fits snugly to almost any trekking pole. Best to keep a spare in case of loss. Otherwise, the rubber cap is a consumable, so it is necessary to take a spare part to replace it. Rubber tips protect the metal tips of trekking poles, reduce the friction between the trekking and road tip for long term use. There is a built-in metal washer inside the rubber tip which protect the rubber protectors from being damage caused by the trekking tips poles. The advantage of the rubber tip: It helps to get extra grip on the rocky surfaces. It helps to reduce noise on rocky surfaces. It protects the metal tips of your hiking poles. It helps to attenuate part of the shock on the stone pavement. Specifications: Material: rubber Color: Black Inner Diameter: 12mm Height: 35mm Quantity: 16 Pcs / 8 Pair < p>Warm Tips: Please make sure the size before you place the order.