Well, dropping 300-350g per wheel makes your fatbike ride more like a gravel bike and less like a dump truck. Spin up is noticeably faster. Tire compliance over postholes is smoother. Still running same 5psi. Currently in the "testing phase" before going out in the deep woods on long treks. One tube is holding air great, the other lost a bit more overnight than I would hope for. Will check back on that, early days. The stem is not metal like a butyl tube, but a plastic material with the normal valve core in it. Assume that the metal doesn't reliably bond to TPU like it does to butyl. And there is no "locking nut" like at the stem of a metal butyl tube to screw down against the rim surface. Thought that was a bit oddly different, but it works just fine. The reported weight is as stated for the tubes. Been using them down to -20C. So far, it's all positives. Note that if your tire bead won't "pop out" Ottalaus says soapy water is fine (in moderation) to lubricate the tire/rim interface and won't adversely effect the TPU. I had more trouble with the beading popping out fully, for some reason, than I've had with butyl tubes. The TPU material is pretty thin (of course), so I wiped out the tire and cleaned the rim contact area thoroughly (then even used shop air to blow out any remaining particles) before install, so there would be no grit to abrade the TPU. Likely overkill, but since they do cost more, I thought some care was warranted. Service/answering questions from Ottalaus has been top notch. Pretty pleased if they turn out to be durable. And, as I run diff tires in the summer, no sealant mess to deal with.

Jay is awesome to deal with and always goes the extra mile with support! He is also on point with great suggestions for upgrades. Ottalaus also has all top notch products!

Faster than expected shipping. The Fatty Stipper install went very well and the air is holding with some sealant. I almost ruined one by tightening the valve before it was all the way through the strip but that was my error. I should have set the valves through the strip before placing on the rim. It would have been an easier installation than it already was. A must for Giant Yukon fat bike rims.

Easy to install, holding up well, no air loss or anything in the first month of riding. So much lighter than the original butyl tubes.

Outstanding service, would definitely use them again.

Looks great, waiting on a build with it!

communication with seller was great as 100% accurate with items..above and beyond transaction

I had an issue with a product I'd ordered from Ottalaus. Jay was quick to offer and send a replacement before I'd even returned the original product. He had me riding asap.

I absolutely love these lights. I bought the evo and hangover last year for myself. Direct from outbound lighting. So this year I wanted to get a set for my son and my wife for Christmas and I come across. Ottalaus on Facebook so needless to say I am very happy that I can support a Canadian company and purchase these lights from you. I would like to thank.Ottalaus for the awesome customer service that I received. My product was here within four days. When opening my parcel, I had a big smile on my face when I seen that you sent me a gift. I would like to thank you for that and I will definitely try to do my part and send some business your way. We are a very big mountain bike and fat bike community here and I will definitely wear my bling that you sent me. Thanks, Brian.

Pretty cool.

just did two hours at -18c with the light on low. 75% of battery left at the end of the ride. (i did wrap a bit of insulation around it)

Light is awesome. great beam, great battery life. Mount has no vibration and the wt is not noticeable when riding.

I was a bit worried about winter run time but I just finished a 2 hour ride at -18C and only used 25% of the battery charge. I did run it on low which was plenty of light with snow and I also wrapped the battery with a cotton tube to insulate it a bit.

The rest of the light is exactly as expected. Great light beam, no vibration in mount, and wt is not really something you notice.

This is a great light!

Ordered a pair of bike lights and had them delivered super fast with some bonus swag to boot. Jay was super helpful answering all my questions leading up to the purchase.

I like the light quality, the button, the light output, the mounting system, the sellers promptness and communication, everything about it!!

The light was a little pricey but worth every penny, you get what you pay for. Buy once cry once. I will have this light forever and im positive itll be problem and hassle free. well worth it, I cant wait to ride in the dark now.

Dropped almost 1lb/500g per wheel after removing the stock "heavy duty" tubes. I use my fatbike year round and swap studded tires on and off my wheelset based on conditions so not having to deal with sealant is a plus.