For all models with the QL2.1 system, except for: Office-Bag, Commuter-Bag, Commuter-Bag Two and Downtown Two Worn, broken or lost mounting hooks? Replace your QL2.1 hooks with a new set of QL2.1 hooks and plastic handle. If the new hooks are too loose on your bike rack, use the appropriate hook inserts for a snug fit. - 2 QL2.1 hooks (16 mm) with plastic handle - 1 pair each of hook inserts in sizes 8 mm, 10 mm and 12 mm