Made with a 3D printer. These parts are for attaching KATO couplers (close-coupler type) to TOMIX, Greenmax, Micro Ace, etc. TN couplers are expensive! Want realistic coupling faces and spacing! This product is recommended for those people. When using, you may need to cut a part of the product, similar to when installing TN couplers. This product includes 100 pieces. Other quantities are available in other listings, or please feel free to inquire in the question section, and we will list them. Requires KATO product 11-731 (sold separately) and assembly. Depending on the track environment (sharp curves, layouts with gradients, etc.), you may need to use 11-730. We also sell pre-assembled versions with couplers already attached, so if you find the modification troublesome or are not good at it, please purchase those. For additional orders, it will be +50 yen per piece, but we will offer a discount for customers who purchase in large quantities.