Parts › Weaver K4S/P2S Adjustment Block Saddle. New Old Stock Image 1 of 1 Weaver K4S/P2S Adjustment Block Saddle. New Old Stock $19.99 For the Weaver Stainless steel series K4. Never assembled part from the Weaver factory auction in 1984. Get notified by email when this product is in stock. <p>Subscribe to our mailing list</p> Add To Cart Added! For the Weaver Stainless steel series K4. Never assembled part from the Weaver factory auction in 1984.