These SRP Ford small block dish top pistons fit Ford, TFS, GT40, Canfield, Brodix Track I, OE, and Dart Windsor cylinder head applications (not recommended for Twisted Wedge, N351, or Edelbrock 7721). They're made from 4032 low-expansion, high-silicon aluminium alloy that's heat-treated to SRP specifications. A wrist pin is included and their CNC-machined ring grooves accept 1/16, 1/16, 3/16 rings, which are sold separately.