These are factory - assembled Kadee #148 Magne - Matic Couplers in a #242 Snap - Together Gear Box. They are HO scale metal #148 Medium Centerset Couplers with the Whisker Centering Spring. The gear box comes with an insulated #242 Draft Gear Box and Lid, and there's a center screw hole for easy mounting. Each package contains two pairs of these great - quality couplers, perfect for your model train setup.

Using these HO scale Kadee #148 couplers is easy. First, find the center screw hole on the coupler and use it to mount the coupler to your model train. Make sure it's firmly attached. When connecting cars, just bring the couplers close to each other and the magnetic force will do the work. As for maintenance, keep them clean from dust and debris. You can use a soft brush to gently clean the couplers and the gear box. Avoid using harsh chemicals as they may damage the couplers. Store them in a dry place when not in use to prevent rusting. Be careful when handling the couplers as they are small and delicate, and you don't want to bend or break the Whisker Centering Spring.