I have to say that I didn’t know this product and I decided to buy it because of the people’s review. However, I’m happy with the product. The quality pf the product is great and it’s easy to use. I think the price is just right for this product. Highly recommended.funciona bien, falta stock de repuestos!Excelente y llego a tiempoI had to replace my old one, let a 'friend' borrow it and it never found its way back home. :-(the new one does the job well. This time no one is going to borrow it. I uses it for glass shower doors install & window replacements. NO building climbingOMG. If you move heavy sheets of anything slick, these are a must have! Bought these for a window install project. After struggling to hoist the windows off the truck at delivery, with two big strong men to help. Two women carried four different sets of 7-foot wide double-paned, mulled-together, double hung windows up a flight of stairs (they're about 200 pounds per window) and installed them by leaning them through the opening then pulling them back in. Whew. Thank goodness we had these suction cups!Yesterday, I needed to move some heavy folding tables. Noticed the nice little blue box of suctions cups on the shelf in the garage as I was debating whether to wait until someone else got home. I used them to carry folding tables by myself. No Problem!Love these things!Awesome suction power! They do not slip. Grip like no other. Carried and lifted numerous windows, a true blessing to have them.These are great and last if you take care of them. I like these especially cuz they're lighter than WPG cups and cheaper.These suction cups work great. We use them for granite, quartz, marble and glass. They hold suction well. My only complaint is that they come with 10 cent boxes. One of the two I ordered actually came with a broken latch on the box. Still worth it in my mind. A nicer box would have made it 5 stars.