5" of 60 degree carbide on a competition style, 1/2" host bar. This runner, in addition to the two, 5/16"-18 x 1" mounting studs, will have a 3/8" ski-stop to prevent the ski from rocking.
Its marketed for Mini Z's but if you know how to weld you could change the mounting studs to work for any brand ski.
It also has 24 studs with the nuts and backers.

The carbides alone from Doo are $86.88 and this kit includes the studs.
I will sell for $50