Review on 🔗 CoZroom Triangle Bed Sheet Fastener: Adjustable Holder Straps for a Smooth Mattress - Pack of 4, Black by Tricia Pence

As advertised. No surprises. They will definitely keep your sheets in place. covers all corners - top, bottom, both sides and all four corners. They seem to stay in place until I take them off to change the bedding. As soon as they appear on your sheets, you will be satisfied. That being said, they're difficult to establish, but that's the nature of working with something under matter. If your bed is against a wall or near walls where space is limited, it will be more difficult for you to set it up. Beds with headboards and footboards also slightly increase the level of difficulty. Again, you keep this item under your top mattress, so it's not that hard to imagine a struggle, especially with king-size beds. As said, once you have them installed they will work great and do exactly what you expect them to. They hold the sheet firmly in place until you are ready to change sheets.