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Question: Has anyone tried to attach this to the glass shower door?  My tiles are not real smooth?
Document: this item would not remain attached to my 4" smooth flat tile or even my laminated bathtub. I positioned it to avoid the seams between each square tile, I tried affixing it dry, wet, oiled, even with honey, and it would lose it's grip within minutes and eventually fall down. Just for fun I tried it against flat glass, and that seems to work - but I don't have a glass walled bathroom, so I'm returning this for a refund. I advise anyone considering a suction cup product to buy the smallest cheapest example and try it first on your surfaces for a few days before investing in more of them.
This handle works well when it first goes on. My warning is that it only stuck on the wall less than 24 hours. I had to re attach it each morning. The tile in the bath I used it in is not real smooth and does have hard water stains. That may be the reason for it not sticking long. Be aware, none of these type of bath & shower grips are  meant to support a lot of weight, just to be used for balance.Nancy
Well, maybe I was expecting too much. The real problem is that the tiles in the shower for this use are not smooth, but have a slight ripple texture to them. Unfortunately, it was just enough to cause the suction to fail. My husband doesn't want to use a permanently installed handle. So, problem not solved as hoped.
The handles are large and easy to grasp. They stick well and remove easily. A few caveats, which are not negatives for this products:-  They are designed to add stability, not to support a person's weight. They stick very tightly, so I believe the real limit is the strength of the wall (you could easily break the tile and dry wall behind it). If you want real load bearing, then you need something that attaches directly to the studs behind the dry wall.-  Attach them carefully so that the entire (large) suction cup is on smooth tile, not on the grouted joints, because suction cups do not stick well to rough surfaces.-  Re-attach them regularly (say, between uses, not in the middle of showering), because suction cups leak slowly and their grip weakens.
I bought one of these from a local retailer and I couldn't get it to stick for anything. I wet the suction cups and it still didn't work. I thought maybe it was just my tile, they are slightly textured but I tried it on the smooth door on the refrigerator just to see and it wouldn't stick to that either! Absolutely useless. Like a dummy I went to a different store and bought a different brand and got the same results. I'm buying a stainless steel one and bolting it in to the studs.
I was able to attach this to the tiled wall in our tub after two unsuccessful tries. It's been on the wall for several days now, and it seems as secure as it was at the start. It provides a great grip in our combo shower/tub. The first two times I tried to attach it it fell off after a few hours. I guess it fell off because I didn't have the suction cups placed exactly in the center of the 4.25 inch, 60 year-old bath tiles in our tub, and the suction deteriorated.
I test each grip daily for looseness before trusting them as handholds for my balance. Once more though, these are not intended to be weight-bearing devices, and neither are my wall tiles. As something to hold or grab for stability though they are excellent and I still give them a 5-star evaluation. Note that I have these attached to smooth ceramic tiles which I thoroughly cleaned with glass cleaner and dried well before attaching the grips.
Please carefully read as many positive and negative reviews on this product, as the product details do not give you it's restrictions. At first, I tried this product on a smooth flat surface, and it was very strong. I weigh 200 lbs. and could not pull it off, and could almost hang from it. However, when I tried it in the shower, which is why I bought it for my 82 year old mother, it didn't work. If your tiles are small so that any part of any of the round suction areas have to lay across a grout line, it does not hold at all.
I believe I would pull the tiles off the wall before jerking the handle off. It is a great safety feature for us who are a bit too infirm to handle slipping down on the slick floor.I would but this product again and recommend it to anyone smart enough to hold it against a smooth tile and push the buttons down. Otherwise, get a tile contractor to remove the tile and set a permanent handle for you.
I was in an accident and used this in our shower. We did not want to put in a permanent handle. Please, if you have a permanent disability, this unit is not for you. You want to make sure you remove it and re-attach EVERY time you shower. The suction cups do not stay on tight after a period of time. I found this out the hard way. Grabbed a hold of it and it popped real loud. Scared the crap out of me. But, if you pull it off, get the cups wet and re-attach it each time you shower or bathe, it will hold you, I promise.
Answer: This has to be on a really smooth tile or glass.  Any uneven surface, even the slightest and it slips off.