B&T style speed loader for your MP5 magazines. Designed around HK & MKE stamped magazines. May not work with polymer magazines. I have included two separate files (TIGHT & LOOSE) depending on your printers tolerances and desired fit with magazines. -LIKE THE B&T; A COUPLE DROPS OF GREASE RAN THROUGH THE CHANNEL WILL MAKE IT RUN MUCH SMOOTHER -WORKS BEST WITH A SHARP EDGED TABLE OR YOUR HAND TO DEPRESS CARTRIDGES .STEP file included if you want to make changes. See video demonstration here: https://www.youtube.com/watch?v=himrMwJ7gn8