The Nerf Knockout is one of the most modded rival blaster that hasbro has released. I made about 6 myself, from single shot dart shooter to a Demolisher rocket launcher. I couldn't find a T-Pull that was "comfortable” to my likings so I decided to create my own.
I printed it on my Bambu P1S:
PETG / Flatside down / Brim of 5 layers wide / 3 or 4 walls.
Other hardware: (I used stainless steel).
5x45mm countersunk screw. H2 / Link to all info: https://www.rvspaleis.nl/bouten/binnenzeskant/din-7991/din-7991-[-]-a2/din-7991-[-]-a2-[-]-m5/7991vo-2-5x45_1
5M sleeve nut A1 / Link to all info: https://www.rvspaleis.nl/moeren/hulsmoeren/verzonken-binnenzeskant/9062-2-5_1
You can do whatever you want with it without my knowledge or approval. I would prefer if you kept attribution, but you don't have to.
Keep on flinging foam, brothers and sisters!