The Kadee #37 Plastic-Shank Coupler Kit in HO Scale is a great choice. It features the Magne-Matic® technology, with a strong plastic insulated coupler, #621 Torsion Centering Spring, and insulated #233 Draft Gear Box. The 30-Series couplers can be body-mounted above or below the platform, with or without the Draft Gear Box Lid, which can be on top or bottom. Each package contains two pairs of these couplers.

Using the Kadee #37 couplers is easy. First, decide where you want to mount them - above or below the mounting platform. You can choose to use the Draft Gear Box Lid or not, and place it on the top or bottom as you like. Make sure to install the 30-Series Torsion Spring between the Coupler Spring Lid and Draft Gear Box, it can be mounted either below or above the coupler shank. When it comes to maintenance, keep the couplers clean to ensure smooth operation. Avoid exposing them to extreme conditions as this might affect their performance. Also, check the Torsion Spring regularly to make sure it's in good shape.