Attributes . ALEMITE 1/4-28 Taper Thread Fittings are used on most cars and trucks, as well as many industrial machines. It is recommended that SAE-LT taper threads be assembled into 1/4-28 UNF, Class 3B, straight threaded holes having a modified maximum minor diameter of 0.2151, to provide 75% minimum thread height.FEATURES:Exceeds 72 hour salt spray testDirt excluding check ballTrivalent zinc platingRoHS compliant . Names