Singer 99K, 201, 237, 328, 401, 630, 717, 935, 1200, 2000, 2210, 4011, 4552, 4610, 4617, 4622, 4623, 4830, 4832, 6136, 6212, 6233, 6267, 6268, 6704, 6705, 7000, 7004, 7005, 7028, 7050, 9005, 9008, 9010, 9134, also Pfaff serger 4762, round double contacts