IBERA 11" Longer Rods One Pair for IB-RA4/RA5 Carrier Rack The carrier rack is made of durable TIG-welded, heat-treated, anodized aluminum. This material is usually used for the bicycle frames and components, so it is as strong as your bicycle. Plus+ allows Ibera trunk bags and planet-friendly reusable bags (IB-BA1, IB-BA14, IB-BA15, IB-BA22) to be mounted with Ibera panniers simultaneously (IB-BA9, IB-BA20) Also compatible with strap-attached bags and panniers.