The TSI-1 enables you to inject the perfect amount of sealant directly into mounted tubeless tires through the valve stem without removing the bead from the rim. The long, thin tube is able to fit all the way through many Presta stems with removable valve cores, for tidy injection and removal of all injectable tubeless bicycle tire sealants.
Worked very well to inject sealant into tubeless tires via valve stem. You'll need to remove the value stem before injecting, which is an easy task. Too soon to say anything about its durability although it seems well made. I'm using Muc-Off sealant. It suspect that it would work equally well with other sealants.
One of the complaints I have read is that this tool only comes with one long tube which might break or become clogged. Mine came with 2 which I appreciate. Easier to use and is nicer to use than my previous injector. Cleans well and extra parts are avilable in the future if needed. I think it is worth the extra money.
Much better than the cheap version I bought on Amazon, which broke after a few uses. This should last a long time. I have only used it once so far, but it is well constructed.