SET2: 1 x rear rack for + 1 x For Seatpost Sleeve set AdapterDuring installation, the protrusion is aligned with the groove at the back of the tube, and then the outer side of the reducing sleeve needs to be coated with glue.which can be fully adhered when inserted into the tube after 6 hours.Tips: It's the Standard Cargo. Fit the "R" model mudguard, If Model is "L" mudguard, you need buy Conversion Block.Name: Bike Standard Racks For Feature: Durable, Stable, LightweightUsed for: Bikeadapter: from 34.9 to 31.8mmMaterial:plastic/Aluminum alloycolour:blackPackage Contents:1 x rear rack for 1 x For Seatpost Sleeve set AdapterOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.