This insert helps with aligning the hex wrenches with the bottom hole of the holder. Though it was designed for this specific wrench set: http://www.harborfreight.com/10-pc-metric-t-handle-hex-key-set-69370.html it should work with similar sets.
hex_wrench_line_up.ipt | 485.0KB | |
hex_wrench_line_up.stl | 460.4KB |