One piece base used on:
Marlin 9, 45, 30AW/AS, 36, 62, 93, 336 (all models, 375, 444, 1893, 1894 (all) 1895, Glenfield 30, Zane Grey, Camp 9 Carbine, 922 M, 989, 22 Rfl
Mossberg 640, octagon barrel or flat top receivers (base length 4.700", .370" thick)