These delrin rail buttons are sold separately. Designed for larger project launching from standard Unistrut style rail. Click on the second image above for dimensions in inches.
Don't buy just one set, get a couple for the range box.
Also available in other sizes, see the website.
Unfortunately we're having to temporarilly make these in house so the price had to go up. We're looking for a new source at the moment to drive the price down. 05-10-17 Bob