Standard Inner Tube – 21" – TR-4 (Center Metal Valve) 🛠️💨

When you’re running a skinny front tire that takes a beating, this tube is the insurance policy that won’t quit. Made from real 100% butyl — not the blended stuff that bleeds air overnight — it holds pressure longer, resists heat, and stays solid through rough terrain. The TR-4 threaded center metal valve locks down tight and installs clean every time. Fits a wide range of 21" front tire sizes, making it a damn reliable choice for riders who expect gear that just works.

The Breakdown

🔧 Built from real 100% butyl polymer for long-lasting air retention
💨 Minimizes natural air loss for consistent tire pressure
🔩 TR-4 center metal valve with threaded hardware and round base
🛞 Fits 21" rims and multiple tire sizes including 100/80-21, 80/100-21, 90/90-21, 2.75-21, 3.00-21, and 90/100-21
🏍️ Works on both front and rear applications
🪛 Standard-duty construction that holds tough without unnecessary weight
📦 Individually boxed with clear valve and size markings
🌎 Ready for off-road, on-road, and everything in between

The kind of tube that stays loyal when the trail tries to break everything else.