Buckeye 3 Axle Trucks are designed to work with Micro Trains Z scale (1/220) Magnetic Knuckle Couplers (#905), Micro trains 33” standard wheels (#950) and Micro Trains Round Bolster Pins (#952) Buckeye 3 Axle Trucks with Micro Trains Z scale (1/220) magnetic Knuckle Couplers are designed to install on Micro Trains 50' Gondola with Straight Sides, Micro Trains 50' Gondola with Fishbelly Sides and Micro Trains 60' Flatcar. Buckeye 3 Axle Trucks with Micro Trains Z scale magnetic Knuckle Couplers are compatible with all Micro Train rail cars and locomotives. Has not been tested on corners sharper then 195 mm curved track.