1、Aluminum kickstands, very sturdy and durable. Large solid rubber tyres roll smoothly across sand, gravel, and road. 2、The top parts of the kickstands are inserted into the kayak bottom scuppers and the EVA cushions help to protect kayak whilst being transported. 3、The width of the unique crossbar is adjustable with a screw to accommodate different placement of scuppers. This kayak trolley is very easy to install and use. the large solid rubber tyres roll smoothly across sand, gravel, and road. It is a great trolley for you to transport your kayak and save your energy. Features: Aluminum kickstands, very sturdy and durable. Large solid rubber tyres roll smoothly across sand, gravel, and road. The top parts of the kickstands are inserted into the kayak bottom  scuppers and the EVA cushions help to protect kayak whilst being transported. The width of the unique crossbar is adjustable with a screw to accommodate different placement of scuppers. Very easy to install into the tyres with two buttons. A great trolley for you to transport your kayak. Specifications: Material: Aluminum + Rubber Loading Capacity: 50kg Tyre Size: 26 * 7.3cm / 10.24 * 2.87in(D * T) Crossbar Width: 29 - 42cm / 11.42 - 16.54in Weight: 1.9kg / 4.2lb Package Size: 54 * 39 * 10cm / 21.26 * 15.35 * 3.94in Package Weight: 2.3kg / 5.1lb Package List: 1 * Kayak Trolley Note: Please allow 1 - 2cm (0.4 - 0.8") differences due to manual measurement, thanks. 1 * Kayak Trolley Note: Please allow 1 - 2cm (0.4 - 0.8") differences due to manual measurement, thanks.