<p>Local Carpet track is requiring nut covers. at first I was less than convinced that would ever work.<br><br>I got a few sets to try from their shop and they shot off like bullets, so i decided to make my own. All need to be printed in TPU. I HIGHLY recommend SainSmart.&nbsp;<br><br>"long pro - hex cover": This is the real winner. Meant for those 2wd rear axles that are several mm long past the nut. these are the ones the track is most concerned about (as opposed to a 4wd front where the nut protrudes, but no axle. The idea here is they actually screw onto your axle. the are designed to go over a low profile nut, and screw onto the threads. The print isnt threaded, but the tpu will self tap. I ran these for probably 20 lipos yesterday and didnt lose a single one.<br><br>"medium pro - hex cover": These are similar to the first ones but not as long. Meant for something like a b84 rear on 7mm rear hex, or a b7 front, where you have like 1-2mm of axle poking out. Again, made for low profile nuts. they dont "screw" on as much, but still do "screw on" a tad.<br><br>"low pro - hex cover": these dont screw on at all. just a flat cap. made for something like a wheeler front, where your nut sticks out far but the axle is buried in the nut. again made for low profile nuts. they are slightly smaller than the nut head, but the tpu stretches a bit. I ran them all day yesterday and didn't lose a single one, though if you have issues, they do stay better if you put "flats to points" on the nut, so basically, put them on so they dont "line up" with the nut.<br><br>as you can see in the photo, if you have a lot of axle poking out, and use the long screw on ones, you can literally hold the car by them and they wont come off</p>