This item is deprecated, use http://www.thingiverse.com/thing:623414 instead. Seat post mount for 27.2 seat posts and GoPro compatible mounts. Extension arm is long enough to mount a Contour or other bullet style camera above the arm. Wanted to make sure this was stiff enough, modified some of the clamp widths. Loosely based on http://www.thingiverse.com/thing:62800 Files are provided in multiple formats for those that want to tinker with them.Created two parts using the following Customizer http://www.thingiverse.com/apps/customizer/run?thing_id=62800, first was a clamp. Use any head you want for the primary as I discarded it. Then created a second extension arm with triple head longer than needed. Converted all pieces from meshes (.stl) to solid objects in FreeCAD. Cut off head from clamp at an 8.5° angle, and cut off the arm at 8.5° to desired length. Combined both pieces together and ran it through the Microsoft netfabb online repair tool https://netfabb.azurewebsites.net/ . This extension arm is a bit longer than the original to accommodate bullet style cameras mounted above the arm, such as the Contour Roam, etc. Use two 3 mm x 15 mm cap screws and two 3 mm nylock nuts to secure clamp on seat post.