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Rival Knockout Cover and Dart holder or rail mount

Rival Knockout Cover and Dart holder or rail mount

Regular price $11.50 USD
Regular price $11.50 USD Sale price $11.50 USD
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The Nerf Knockout cover allows you to add a picatinny rail to the side of your knockout, or storage for 4 darts or 8 darts.


• Styled to fit the knockout perfectly. 
• Add a rail, 4 dart holder or 8 dart holder for either side.
• Available in multiple colors

• Materials: PLA Plastic
• 3D Printed

 Knockout blaster
 Knockout spring
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We print primarily with Proto-Pasta HTPLA and PLA. Check out our full range of colors here.

3D printed parts should not be left inside hot cars or excessively hot environments.

Customer Reviews

Based on 3 reviews
Great Product

Fits as intended with no slop. Shipped with hardware preinstalled. Good print quality. Would buy again.

Kurt T.
Perfect cover + Functionality!

Modded my Knockout and wanted something to cover up the body gap between the shell halves. This fit like a glove! The print quality is very high and precise. To get the pieces to fit well I threaded the bolts through the body and tightened the nuts before assembly to pull the nuts all the way into the body halves. The nuts aren't coming out and it fits great onto my Knockout! I'm ordering a 2nd one for another Knockout I'm building and getting some additional rails too! Awesome product to add back some dart storage if you're converting to half darts or want a picatinny mount for a light/laser or whatever tactics you want!

Cool concept but it doesn't work. At all.

So I ordered one of these hoping to add some dart storage to my half-dart firing Knockout but I have not had any luck with it. The first issue I had with this product was not being able to fit the nut into the body of the cover which meant I could not screw the 2 body pieces together. I contacted customer service and quickly received a replacement. I was expecting the installation process to work this time but sadly that wasn't the case. I was able to fit the nuts into the cover body now but then I ran into a different problem: the head of the screw that holds the body pieces together would not fit in the hole. I took out the original body piece that I had to see if it had the same issue and while I was able to force it down the hole, I was unable to get it to turn which meant I could not attach the 2 body pieces together. After that I decided to throw in the towel and give up on it.