There's not much one can comment on such a basic piece of astrogear like this extension tube. I found it to be nicely built, the clamps worked solidly (they don't feel flimsy in the least), and I really appreciate that there are two of them - that makes for a more positive locking of the eyepiece/diagonal/Barlow lens that you might be adding to the "business" end. I also have a TeleVue equivalent extension tube, and I can't see that much improvement for 2x the price.
A good piece of functional gear at decent pricing. Recommended.