The 20-Series Kadee? Magne-Matic? Couplers are designed for either Talgo (truck) or body mounting. The 27 Kadee? Magne-Matic? Coupler features a very strong plastic isolated coupler, 634 Centering Spring, (same gear box as the 5 Coupler), insulated 232 Draft Gear Box and Lid with side and center screw holes for mounting and the (20-Series draft gear box) insulated 213 Universal Adaptor Plate. The 27 Coupler easily installs in existing Talgo-mounted draft gear boxes or can be body mounted with supplied 232 draft gear box (5 Draft Gear Box) with side and center screw holes for mounting or with the supplied 213 Universal Adaptor Plate (20-Series draft gear box). Note: The 20-Series assembly may be mounted from the top or mounted from the bottom but the 634 Centering Spring must be always mounted on top of coupler shank. Two pair per package