Strength and rigidity of Quick Install pushrods are second only to heavy-duty one-piece pushrodsTube material starts out as 7/16” rod OD, then gets turned down to 3/8” OD leaving heavy duty 7/16” - 20 threads for the base and jam nut0.134” wall thicknessJam nut slides up the pushrodBase then loosens up into the pushrod to allow Quick Install accessIndividual length exhaust and intake pushrodsInstall without the removal of rocker coversCorrect pushrod/lifter adjustment requires starting with fully pumped up lifters.Quick Install pushrods have 7/16” - 20 threads per inch. 0.050” adjustment per turn. Two turns = 0.100”.