This attachment is intended for beams with a round cross-section. Shields the screw against water, dirt and vandalism. It prevents the device from unscrewing due to the total lack of access to the screw. Fits round beams Ø80 -: - Ø160 Available sizes: Ø40 with screw hole M8-M10-M12 They are produced in 4 basic colors - yellow, red, blue, green, but at the customer's request we will make any other color. Material: Polyamide PA6