This is a handle cover designed for the Nerf Stryfe. It goes over the sling loop at the bottom. You can permanently glue/epoxy putty it to the strap loop or use a screw and screw hole at a location of your choosing to hold the halves together. (There is no screw port in the design due to differences in people's builds so you may have to drill your own).

I can't guarantee that this part is perfect as I am still not a master of 3D modeling, so I have included the Solidworks files so that you can edit them to work better if necessary.

As usual with my Thingiverse uploads, feel free to use and edit these files for your blasters if you have your own printer as long as you do it non-commercially (don't sell them please; that's what I plan on doing once I perfect them).

-Mitch from BlasterPrints

EDIT: Part scaling and fit fixed and tested as of 10/9/2017. It should fit your blaster now with minimal gaps.