Part#MTkitMudGd3pc516fine - Mirror Topz 3 piece 5/16 UNF [fine thread] mud guard premium bolt kit.  This kits consists of 1 x premium polished 316 stainless steel bolts, washers and spring washers. Suits most large size American and Australian Fords from 1950's, into the early 60's. The mid to late 60's Ford had UNC course thread where the earlier Fords like the compact fairlane had this fine thread.  It only really matters to what thread type you have in your existing captive nuts.  It may pay to check to see that no one has put later model captive nuts on your car before you buy. This polished stainless bolt kit is intended for applications where there is a captive nut or captive pressed metal clip fitting that is retained on the body to where the body panel is to be mounted.