This gear is designed for the 1/6 Scale Anderson Ta-152. For Dave Andersen's website, look at http://www.mnbigbirds.com. We use our 1/5 scale upper main mechanisms with 5/8" diameter oleo struts. Axles installed at angle specified by manufacture and comes with a complete large air system included! See part number 1400 for large air system description. For realistic retraction and extension gear speed, look at our Deluxe 4 Way Valve. Order 1410E when ordering the gear and save $$$$.