This listing is for a 48mm ribbed heavy duty cast clamp designed for trailer jockey wheels and prop stands. It features a 48mm diameter with ribs to enhance grip and prevent slipping, making it ideal for heavier trailers like car transporters. Constructed from steel with plating for corrosion resistance, this clamp ensures durability and longevity. The mounting holes are 17mm wide and spaced 124mm apart at their closest point, typically secured with M12 bolts and a thick repair washer. This is a high-quality, OEM standard part that fits all ribbed jockey wheels and ribbed prop stands.