THK: .025", .050" Chevrolet - 240, 250, 262, 283, 305, 307, 348, 350, 366, 396, 400, 402, 409, 427, 454 & Inline 6, Except 29 1965-2005 Chevrolet's Bel Air, Blazer, Caprice, Chevelle, Impala L6-4.1L, V8-5.0L, 5.7L, 6.5L, 6.6L, 7.0L, 7.4L engine. 1961-2006 GMC's C15, C25, C35, G15, G25, G35, Jimmy, K15, K25, K35, Sprint L6-4.1L, 4.4L, V8-5.0L, 5.7L, 6.5L, 6.6L, 7.4L engine. GM Flywheel Shim