These glasses were a very cute addition to our Glow in the Dark birthday party we styled. However, there were a couple of the sticks that weren't lighting up and I had to use some from the other glow sticks I had on hand. But overall I would recommend them because the kids loved them as they carried them around and it kept the glow with them.These cups are made of a super thick plastic. Not the flimsy stuff I was expecting. The glow sticks that come with them, fit perfectly. Once you get the hang of how they install, they are a breeze to put in and wow did they last. We lit them off around 9 pm and they were still glowing, not as bright, but still glowing the next day at 7pm. You can certainly wash these and reuse, if you chose.These were so much fun for our party. Worked as expected and everyone really enjoyed them. The only reason for the 4 stars is that the glow stick didn't fit completely into the lip of the cup. No big deal though it just stuck out a little.These cups are so awesome! My twins had a glow party, and I bought these thinking they would be a better choice than to put glowsticks directly in the cups. Everyone loved them, and asked where I got them from. They were very easy to assemble, just push the glowsticks in the rim, and done! They glowed for at least 4 hours! I'll probably purchase more for next year's July 4th party!They were pretty cool , only reason I gave them a 4 is because Not all the glow sticks lit upCan't wait for vacation to play beer pong with these. Looks like the standard glow stick will fit in the slot under the brim. Way better than getting the clear cups and having to push the glow sticks to the bottom of the cup.The cups were used for my daughters sweet 16 celebration....in the arcade room. They were definitely a big hit and made it known that we left no detail unthought of! I will be ordering a neon blue or green set for my sons bday celebration!Should have paid attention to the stated volume. The picture looks like a typical plastic cup size, but they are short and squat. Definitely only a 9 oz cup. Kids liked the glow. Easy to assemble.