Mountain bikers, these MOHEGIA tires are built to handle some serious terrain! The 26x2.125 inch size is perfect for most mountain bikes, and the ETRTO measurement is 56-559mm if you want to get technical. The continuous raised knobby pattern gives you awesome traction and control on all sorts of surfaces - we're talking rocky paths, muddy trails, cross-country routes, you name it. They're made from high-quality rubber that's both sturdy and reliable, with good shock absorption and wear resistance. The TPI is 30, and they can handle up to 40 PSI (that's 275 Kpa or 2.75 BAR for our metric friends). The package is actually a complete kit - you get TWO tires, TWO inner tubes (26x1.75-2.125 inch with 32mm Schrader valves), and TWO tire levers. Everything you need for a tire replacement in one box! The tires are folding design, which makes them lightweight and easy to carry as spares. Important note though - since they come folded in the package, you'll want to unfold them and let them sit for 1-2 days before installing so they can return to their proper shape. The puncture-resistant construction means fewer flats when you're out on the trails, and the tread pattern really bites into challenging terrain. Whether you're into off-road cycling, dirt trails, or just need reliable replacement tires for your daily MTB rides, these deliver performance and durability at a really reasonable price. The quality feels solid, and they mount onto rims pretty easily with the included levers. Seriously, if your current tires are worn out or you're just looking for an upgrade, this complete tire kit has you covered for your next outdoor adventure.