YUNSCM 2-PCS 20x4 Heavy Duty Fat Tire Tubes Schrader Valve Premium Butyl Rubber 20 Bike Tubes Compatible with 20x3.5/4.0 89/102-406 E-Bike/Mountain Bike/Street Bike Bicycle Tire Tubes

These were advertised as "heavy duty" 20x4 inner tubes. When I opened the box and took one out, I was very pleased at its heft and weight. It was much weightier than the tubes that the bike came with (that kept getting punctures!) I had had several flats in the front and finally one on the rear that I could not repair (it was pretty big!) So, in searching for hefty tubes, I found at least one other brand at a higher price point and read a few of the reviews. I went back to the "Amazon Choice" that had come up earlier and am glad I made that choice! They fit fine and were easy enough to install. I mean to say, it's changing a tube on a bike, something that I had done many times when I was young! I was pretty worried about these, if they would hold up, if they were heavy, heavy duty enough for the type of riding I do! Well, so far, I've put about twenty miles on them over the same graveled and muddy road surfaces that blew out the first ones after about a mile or two. No punctures to report. Well, not yet anyways. Only time and continued riding around the graveled and muddy trails will tell on that! I'm glad I got them is the bottom line. They fit fine, seem to be heavy duty enough, and were easy enough to install.

A grand replacement that hasn't failed me yet! Feels just like the one that came with my e-bike. My previous one had unfortunately popped a while back, and although it was difficult to install (through no fault of the tire's, just how the engine and wires wrapped around the wheel), it appears to be doing a good job of lengthening the time before I have to do that again! Huge plus in my book!

Well when I first opened package I could feel it was thicker rubber. It fit really good and is holding up pretty good not bad for 2 tubes for the price

Heavy duty.Good quality.Great price.Very happy with this product.

- Compatibility -I used this to replace the tube in the Front Tire of my AddMotor 'HEROTRI M-365X'.I expect, it will fit the back tires equally well.- Durability -The tubes seem hefty & durable, maybe even more so than the original tube I replaced. I expect that the thick butyl rubber construction will make this replacement outlast the original.- Ease of Installation -Everything fit great & installed easily. The whole process took less than 30 minutes.This install was much easier than my previous experiences with my mountain bike & electric scooter.I had been a bit nervous before the installation due to the electric motor being located in the front wheel, but it was not an issue.Big thanks to AddMotor engineers for making the replacement quick and easy with an unpluggable powerline to the front motor.- Tools -3/4" WrenchTire LeversZip TieI used a 3/4" wrench to remove the wheel.I used a cheap pair of tire levers that I found in my garage to help remove & replace the tire. I'd suggest getting an inexpensive pair, or using a couple of flat head screwdrivers. Not a lot of force was required, but they defiantly made the job a lot easier.Also, I used a zip-tie to help secure the power cable after re-installation.

Tires were perfect fit!! Ride smooth and fast.

Works great

HOWEVER they were clearly to large when replacing the front tube.. So I'm very surprised and DISSAPOINTED!!