The kit is made from tough TPO plastic, also the entire kit is made by us here in the USA! What size tire will fit? That's really up to you, but we can safely say that on a stock height 4x4 Sprinter, we can run a 285-75-16 BFG AT. A slight amount of trimming was required, but it does work. A safe size would be the 265-75-16, plenty of space and zero rubbing.Hopefully most of you have a powered drill, some good drill bits and basic hand tools. A T25 torx bit screw driver is also needed. Nope, all the hardware you're going to need is included. This item is in the category "Vehicle Parts & Accessories\Caravan, Campervan & Motorhome Parts & Accessories\Other Caravan & Motorhome Parts & Accessories". The seller is "campervanculture" and is located in this country: GB.