One star because it works or it doesn't. In my case, the new injector, with the new cheap plastic fitting does not work. I bought a replacement injector after having used my old injector for the past several years. My old injector had a brass fitting and worked great. The new injector has this piece of junk plastic adaptor. I could not get it to screw on to my presta valve at all. I ended using my new injector as spare parts for my old one. Stans needs to get rid of the substandard plastic injector and go back to the brass fitting.
Riding tubeless for a couple of years now. Got the tire mounting down, but really no way to avoid slop and wasted sealer, until now. 20 mins to to pull tire, clean rim, replace stem, replace tire, and fill without a drop on the floor. Already bought a second to give as a gift.
This does not fit on presta valve stems. If dual-threaded means that it can thread onto a presta valve, it is not dual threaded. I even tried turning a valve extender upside down and it would not thread into the injector. I don't see any way to use this with a presta valve or valve stem.
I use my Stans sealant injector for both Stans No Tubes sealant (for our mountain bikes) and Finish Line sealant (for my gravel bike). It works great for getting a measured quantity of sealant into my tires. Its easy to clean, store and re-use.
Maybe the best $10 I've ever spent on bike gear. I've tried every other method for adding sealant to my tubeless tires and nothing is as easy and clean. The brass adapter makes a tight seal on the valve so all the sealant goes into the tire not on the floor. Shake the bottle of sealant and squirt it directly into the injector and you don't have to worry anymore about the sealing crystals settling out and being left behind when you add sealant. Are there cheaper ways to do the job? Yes, but do yourself a favor, don't get cheap at the wrong time.