The file 'M249 Bipod Retainer 3D Printer Model' is (stl) file type, size is 7.4KB.
Picatinny rail retaining piece for the 6mm Pro Shop M249 ultralight. I designed it to work with the original screw that comes with the replica (3/16x1 3/16). You could possible use a 5mm x 32mm bolt.