This is a wheelie bar kit, built to accommodate a damper to absorb the impact of a wheelie and built with 2 wheels instead of 1 to help stabilize the balance of a wheelie.
If I make this available for sale... Some M3 threaded rod, a 5mm bar, a few bearings, a few nylock nuts, and a few screws and grub screws, will be needed to make this kit work. Due to the printing process some redrilling of the holes might also be necessary. If so then a 3mm drill bit and a 5 mm drill bit will be required. Some basic skills, such as using a hacksaw, drilling, filing and sanding, will be required but, if you're in this hobby, you'll probably have those skills anyway.
If I make this available for sale then I'll make a better list of parts and tools.