Morton Glass Fiber Polymide Multiple Lobe Knob， Fluted Rim， Threaded Hole， 1/2"-13 Thread Size x 0.79mm Thread Length， 2.48mm Diameter (Pack of 2)</br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br><img src='http://ecx.images-amazon.com/images/I/51cBJ7cW-TL.jpg' noproxy></br><img src='http://ecx.images-amazon.com/images/I/51bDL6Hb%2B6L.jpg' noproxy></br>