1/4" (6.4mm) Hole Size Head Diameter: 1/2" Stem Length: 15/16" Black Nylon Engine Mount Heat Retainers Compare with: Auveco #14757, Ford # N804448, Crest / Midwest # CRX604, Disco # 9446PK, 9446B, Wurth # 150159243, Kimball / Midwest # 12569