Instruction: Answer the given question by extracting information from the supporting document.

Input:
Question: What is the length of these?
Document: Nice concept, but the push button retainers that regulate the elastic band length have no strength.Once you wrestle the bands on, the adjustment instantly loosens.If the adjustment clips are made stronger, this would be a good product.Too bad!
I really like how they grip tight and because you can adjust the length, you really can get a snug fit. I hate wrinkly, bunched bottom sheets. I am happy I got these and spent a little more.
I bought two other types that were less expensive and neither worked very well and broke easily. This set holds more in its gripper and I can adjust the length after the fasteners are in place - much easier to work with that way.
When I used sheet suspenders which span the entire length of the mattress this issue was never a problem because even if they came loose the clips couldn't snap back on you because they were much farther apart, and the weight of the mattress held them down.You have been warned!
This works absolutely wonderful. I used to fix the fitted sheets every night before bed, this keeps the sheets on perfectly. The button doesn't hold quite well enough, but it isn't really needed, just use them at full length.
Ugh, it annoys me when the bottom sheet comes off the bed. Put these on, and NEVER have that problem again.The adjustable part is a waste though. Just put them to full, unadjusted length, and then clip them to the sheets. Much more simple, and the adjustment slips otherwise.Recommend these.
These work alright if you let the length out completely and attach them to the sheet. The little clips that are supposed to make them shorter aren't strong enough to hold in place so you end up stretching them out completely then attaching to the sheet. Good enough I suppose.
my sheets aren't deep enough for my new pillowtop and these straps have kept them in place for over a week now.I've maxxed the length out so I'm sure they wouldn't work for a mattress deeper than 9".I tried to cancel my order b/c i suspected the other reviews to be fake, but they shipped too fast but I am happy with them.
While the ends sticking to the sheet do a great job and never come loose, the plastic stuff in the middle used to adjust the length seems to be just there for decoration, it slides back to the loose position on its own. Since all four units I received do this, I doubt that I hit upon a faulty set just by coincidence.
These straps are awesome! They stay in place and hold your mattress cover / sheet in place. The length of the straps is very nice, because it can be difficult to determine exactly where to put the clamp on your sheet before your sheet is over your mattress. The adjustable length of the straps eliminates this guesswork -- you can tigthen or loosen the straps once they're on for a sure fit every time!
Answer: 12 inches. They clamp 4-5" on each side of the corner of the sheet and slip over the mattress.