This is an inner mold for ZH Racing rear tires, commonly used in Hang-On Racers. It is the "A (Mild)" type. Made with a 3D printer. The product in the first photo is what will be sent. (The exploded view in the third photo uses the B type (red).) Measured for ZH rear tires, it's made to have a gap of a few tenths of a millimeter with the tire. Compared to B, it has a slightly flatter profile, resulting in a more stable specification. If you've "tried the B inner" and want a little more stability, please try this A. Weight is "16.2g for the inner only" and about "62g with tire and wheel". The dimensions of the wheel and inner are appropriate, so "you can set the tire without adhesive" (photo 4). (If you are using a high-power motor and feel uneasy, please use adhesive.) After a year of making and testing, changing the shape and testing again, I've created something that roughly meets the required conditions. I hope you will try it. Shipping is via "regular mail". Instant purchase is OK without questions. By the way, I am the aforementioned "Chevron Models". Made with a 3D printer (0.1mm layer thickness for precision) and assembled and finished by hand, so I can't make many. Therefore, it cannot be distributed through wholesalers or retailers like our other products. (We have set the price excluding the markup for direct sales.) Please understand. Thank you. Type...Radio Control