Ultraverse Fat Tire Liners Tube Protection Against Flats, 20, 24 and 26 inch x 4.0 tire Size, Durable Extruded Plastic Shield for Puncture Free Bike Rides – 2 Pack

I ride a fat-tire bike often on gravel trails and some thorny back roads, and flats used to be my biggest headache. Since adding these Ultraverse liners, I’ve noticed a real difference. They install between the tube and the tire, creating a barrier that thorns and sharp rocks have a much harder time getting through. The material feels tough but still flexible enough to roll smoothly. I’ve already logged a few hundred miles with no flats, which is a big win compared to my usual patch kit routine. Installation took a little patience to get them seated properly, but once they’re in, you forget they’re there—until you realize you’re not stopping every few rides to fix a tube. Pros: Solid puncture protection for fat tires Durable material that doesn’t feel flimsy Helps avoid mid-ride flat repairs Comes as a 2-pack for both wheels Cons: Adds a bit of weight (worth it for the protection) Installation can be tricky the first time If you ride where sharp debris or thorns are common, these liners are basically cheap insurance. I’d rather spend a little extra time installing them once than deal with a flat in the middle of the trail again.

I recently got the Ultraverse Fat Tire Liners and they’ve been fantastic for my rides. They offer great value for money, especially considering the quality and durability of the material. The thickness feels just right — not too bulky but solid enough to protect against sharp objects like glass, nails, or rocks. The liners are comfortable to use and fit well inside my tires. I also like that they are slightly sticky, which helps them stay in place during rides. Another great feature is that they can be trimmed for smaller tires, making them really versatile. Overall, these liners work exactly as promised, adding extra protection without compromising comfort or performance. Definitely a must-have for anyone who wants puncture-free bike rides.

This is a money saver . Good quality and the fit was perfect. My son hasn't got a flat since

The liners themselves are good for protecting the tube from small punctures or objects that don’t have enough force to go through it. However, don’t expect them to fully protect you from something like a broken glass bottle. Since they’re thick, the glass went through the liner like butter, and I had to replace both the tube and the liner again. I give it 4 stars for two reasons. First, the material is very stiff on the sides, and since it has no curve at all, installing it can be a bit tricky. On top of that, it makes the bike somewhat unstable. You won’t notice it at high speeds, but at medium speeds you’ll feel the handlebar wobble a little bit, something that didn’t happen before. I’ve been riding for 2 months with the latest liner I installed, so it’s not just a matter of waiting for it to settle in. The second reason is that it sometimes prevents the tube from fitting properly, causing it to shift outward since the rubber can’t take its natural shape. I had to manually bend the liner a bit so the tire could seal correctly and both the tube and the liner could sit in place. If I had to say whether I recommend it or not… honestly it’s both yes and no, because it has worked for me, but I’ve also had those drawbacks. I also won’t talk much about the price, because I can’t say whether it’s justified or not (From my personal opinion, a little expensive, everyone can have a different or similar one). It’s one of those products that leaves you unsure about buying it, but if we talk about safety, it is worth having liners inside your tires—they’ve saved me several times.

These tire liners appear to consist of a 3mm thick strip of high density polymer that's a lot tougher to penetrate than the soft rubber of bicycle tires and tubes. Installation went fairly smoothly. My son had one side of a new tire on the rim, inserted the innertube and partically inflated it, then slipped the liner strip in behind it, got it all aligned, added some air, checked again, then fully inflated the tire to 20psi. Keeping tire pressure minimal for conditions is also an important aspect of limiting punctures because highly inflated tires offer more resistance to deformation, so instead of "giving" when a narrow object presses into them, their firmness makes it easier to be punctured. So far, so good, and though I don't expect these liners to prevent something like a screw, or nail from punching through, they will absolutely stop punctures by those tiny little thorns and glass shards that caused the three previous flats on his tires. I was one step away from shelling out the big money for those fancy inserts that show 15mm of thickness between innertube and road surface until research revealed that's a marketing hype, because as soon as th tires are inflated that porous foam compresses down to just a few mm and is pierced as easily as a normal tire with a bit of added thickness. At least these inserts are a hard plastic material that will definitely defeat much of the tiny stuff that causes flats.

This is a thick, strong, and reliable material. It really catches nails, small stones, and glass, preventing them from reaching the tube. My bike has practically turned into a “tank,” and now I ride to work without worrying about getting stuck in the middle of the road. One important thing (and an honest warning): Installation requires patience and care. The strip is quite stiff, so I strongly recommend warming it up with a hair dryer or leaving it in the sun to make it more flexible. And most importantly, make sure the edges are not sharp and don’t overlap too much — otherwise, it could puncture the tube. It takes a bit of effort, but the result is 100% worth it!

The truth has surprised me. They are easy to install and since I put them on, I have not had a single puncture, not even on roads with stones or thorns. I like that they don't change the feeling when rolling, it's totally worth it for the peace of mind of not having to stop to repair the tire. The material looks resistant and fits well on wide wheels. In summary, a very useful purchase if you use the bike daily or in rough terrain. I totally recommend trying them. 💪

Update review, solution to pinching/digging: These things work good, but even when you round out the edges, it still pinches my tubes due to the flat ends that dig into the tube. My solution will involve sanding around the sharp flat ends to also round those out and prevent anymore digging into the tube. The seller should provide sanding tools for this since there’s no way around it due to having to cut off excess material. Cutting off the excess is always going to leave the flat ends sharp enough to dig into the tube. Solid product that does its job, but also causes issues that you need to get crafty with to fix. Luckily, this issue can theoretically be solved by sanding out the flat ends after trimming off excess material. Original review: Pretty sure these pinched my tube due to how much the end of the liner curls when trying to insert into tire, then the curled edge digging into the tube (yes I cut the ends into a rounded shape). I thought I straightened it out enough but apparently not. If the design can change to something that doesn’t leave the final bit of liner curled up so much this issue could’ve been avoided. Besides that, if installed properly, these will definitely protect you from flats. The couple of days that I rode before they pinched the tube, the ride felt smooth, like they weren’t even there. All in all, this is a good product but you have to straighten out the liner before putting this in.