This is a drop in replacement for the front end of the Rival Pilot. To install, put a 16x1.5mm o-ring (or any 1.5mm thick o-ring that fits) in the o-ring groove on the outside of the tube portion. Put this 3d-printed part inside the stock, rival ball accepting, breach (you will need to remove the hop-up). Then button up the blaster as normal.

This has 3 printed parts to it:

Inline Frontend Inline Mag Barrel Shroud The inline mags may need to be sanded to ensure that they drop out the way you want them to. To load the inline mags, push 4 darts into the tapered opening at the top. The barrel shroud has an integrated Trivictus PCAR, which can be found here: https://www.thingiverse.com/thing:5174583

This mod also plays extremely nicely with the manual break action mod that can be found here: https://www.thingiverse.com/thing:5830514

Happy printing! If your inline clip gets stuck inside the barrel (it happens sometimes, I think it is genuinely dependent on humidity and temp) Unscrew the barrel shroud a bit, and it should drop right out.