Ultraverse 20 x 4.0 Fat Bike Inner Tube Set — 2-Pack with 32mm Schrader Valves, Butyl Rubber

Ultraverse 20 x 4.0 fat bike inner tube set (2-pack) with 32mm Schrader valves provides a durable, easy-to-fit replacement for 20"x4.0 tires so you can get back on the trail fast.

These Ultraverse inner tubes are engineered for wide fat-bike tires and built from butyl rubber for dependable air retention and puncture resistance. Each set includes two tubes with standard AV (Schrader) 32mm valves and comes with tire levers to simplify installation. The tubes are sized specifically for 20-inch wheels with 4.0" tire widths, making them suitable for fat-tire mountain bikes, e-bikes, city cruisers and some gravel rigs that use the wider 20" format.

Will these tubes fit my fat bike tires?

Yes — the tubes are cut and molded for 20-inch wheels with a 4.0" tire width. The nominal dimensions mean they will sit comfortably inside standard 20"x4.0 tires without stretching or bunching.

• Compatible size: 20" x 4.0 (fits a range of 3.8"–4.2" tires)
• Valve type: 32mm Schrader (AV) for pumps and compressors
• Two tubes in the pack for spare or immediate replacement

How durable and puncture-resistant are these inner tubes?

Made from quality butyl rubber, the Ultraverse tubes balance flexibility with toughness for everyday riding. They won’t eliminate all flats but deliver reliable air retention and withstand common trail hazards better than cheaper alternatives.

• Butyl construction for slow air loss and resilience
• Reinforced valve stem seat to reduce leaks at the valve
• Suitable for rugged terrain and varied weather conditions

How easy is installation and maintenance?

Installation is straightforward and accessible for riders of all skill levels. The package includes two tire levers to help remove the tire bead, and the 32mm Schrader valves pair with most pumps and electric inflators for fast servicing.

• Includes two tire levers for prying and seating the bead
• Schrader valve works with standard bike pumps and air compressors
• Quick to inflate and simple to patch if needed

What riding conditions are these tubes best for?

These tubes perform well across recreational and performance use where wide 20" fat tires are used. They are suited to snow, sand, loose dirt and mixed-terrain rides where the extra tire volume improves traction and comfort.

• Ideal for fat-bike trails, beach runs and snow riding
• Works for commuter or e-bike setups that accept 20"x4.0 tires
• Good balance of shock absorption and tire stability

Who is this for? Riders who own 20"x4.0 fat tires and need a dependable replacement or spare set will find this Ultraverse two-pack ideal. It’s aimed at weekend trail riders, coastal cruisers, urban e-bike users and anyone who prefers the Schrader valve for quick inflation. The included tire levers and robust butyl construction make the set a practical choice for home repairs or a backup for longer trips. If you want a straightforward, compatible inner tube that restores ride quality and keeps you moving, this Ultraverse 20 x 4.0 inner tube set is built to fit those needs.

For questions about fit or to confirm compatibility with a specific rim or tire model, consult your bike’s specifications or contact Ultraverse customer support through your sales channel.