A decaleur is a front handlebar bag holder which attaches to the stem or steer tube of the bike and helps stabilize the bag. The decaleur is not meant to be weight bearing - Gilles Berthoud and Ostrich bags are meant to sit on the front rack. The decaleur gives you space for your hands and allows quick disassembling for removing your bag from your bike. You can click on the video tab above to see how these work. Three versions available- one for threadless and two versions for quill type stems.
AH - A-head type, or "threadless", stems
H - Horizontal bolt quill stems (Nitto Technomic and Technomic Deluxe stems)
V- Veritical bolt quill stems (Nitto Dirt Drop stems MT10)