Steel,MPYA/M5DA 1st/Low Hold/ 2nd/Rev .079" (20T.)(3.756" ID (Also M5DA 3rd Clu)(Also BAYA/BYBA/B7TA/B7VA/B7WA/M7WA 4th Clu #120)(Also BAYA/BGFA/BVGA-5/BVGA-6/BVGA-7/BYBA/B7WA /MGFA/MGHA/M7WA 5th Clu #120)