THULE th591 Proride / ProRide 591 Parts for T-slot installation are included. Parts for square bar installation are not included. Also, the wheel straps (2 front and rear) have been discarded due to aging. You will need to prepare replacement parts (part number TH1500034358) separately. I think the straps on used items are likely to deteriorate and tear easily, so it's probably safer to get new ones. For online shopping, the spare parts sales page of the importer, Abe Shokai, is the cheapest and most reliable.