One-piece base for Winchester 70 Long Action (same hole spacing) 670 and 770. Made of aluminum with tight tolerances. Note: The handiest way to pinpoint the correct base for the Winchester 52 & Winchester 70 Long Action Rifles is to check the spacing of the tapped holes for the rear base and compare it to the hole spacing for the front base. For hole spacing the same, Model 70, use 47+ 46.