The description on-site states that the material is TPE, and unless you can read Japanese then you'll have to take their word for it. The box is covered in Japanese writing so I wasn't able to verify this. TPE is slightly porous so you'll need to use condoms when sharing.
As far as the properties of the material go, it's very soft, stretchy and squishy, much like the patented Fleshlight Superskin. It has a very realistic feel to it, without the annoying and finicky cleaning or lube restrictions of Superskin. Inside there are several raised nubs that look sort of like a series of dashes all around the sleeve.
The sleeve is pretty basic, as far as male masturbators go. One end has a hole for insertion and it works like an extension of your hand when you jack-off. It's lightweight and easy to use. The textured inside adds a little variety. The material is stretchy, suitable for a wide range of penis sizes. While there isn't any clever beer can, flashlight or plastic case to hide it in, it's small enough to tuck into a drawer if you need to hide it. At about 6" long, it won't take up much space at all. The great thing about this sleeve is the development of a comparable realistic material at a very affordable price. You can squeeze and twist it as much as you like, for a most enjoyable hand-job.
TPE is easy to clean. A little anti-bacterial soap and warm water should do the trick, or a commercial toy cleaner. The sleeve is durable so you can flip it inside out and let it air dry, which you will want to do before storing it. TPE is compatible with silicone and water-based lubes, unlike the higher end sleeves, so you can feel free to use all of your favorite lubes when you play. The material isn't tacky or sticky, so you won't find yourself picking lint or pet hair off of it before each use. You may still want to stash it in a Ziploc baggy.
My husband's opinion of this hinged upon the price. He said it was nice, but if it was any more pricey than the lower end Tenga products it wasn't worth it. After finding out it was around the same price range he said either would be a great option to get a feel for what you like before you sink a bigger load of cash into the popular Fleshlight or Tenga Fliphole. These sleeves would, of course, be your comparison to the Fleshlight.
While he prefers the higher end sleeves, he enjoyed the no hassle cleaning of this one as well as the ability to use his favorite silicone lube with it. He also enjoyed the ability to squeeze and apply pressure to anywhere he desires while twisting the sleeve to feel the textured inside. It has it's pros and cons, like most things, but it's ultimately an enjoyable product.