Not Schumann's.

That's what mine were supposed to be.

After communicating with Clay Smith, Topline Hylift Johnson, and others, I learned that Topline supplies lifters to Clay Smith, Isky, and Comp Cams. The Comp Cams lifters are advertised "Made in America," and Toplines are made in Michigan. After getting a prompt refund for the Taiwan lifters, I ordered a set of the Comp Cams lifters from Scoggin Dickey in Lubbock, TX. 

i found 4 lifters from ford tractor(ova head valve) they are identical toY blocks,except have a small grove for a snap ring which would make chaging cams less risky.lockaly very expensive10$ @ cn.