Replace small parts packed. Spare parts for 1023 & 1025 couplers. Package contains 3 draft gear boxes & lids, 12 coupler centering springs, 12 truck restraining springs, 3 coupler shanks, 6 00-9- x .187 screws, 6 00-0090 x .112 screws, 3 bolster pins, 1 coupler instruction sheet, 12 coupler trip pins.