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Question: How many of these can I safely stack under a bed?  I need to add about 4 inches of space.
Document: I just needed a couple of inches more space under my bed to store things. Every other product I found gave me way more lift than I needed. These risers are perfect, sturdy, well made, and can even be stacked if I want to add some more lift.
They stack very nice and neatly, I can use them in different ways and doesn't take up much space as they are also very strong ! !
I was worried that my King size bed would not fit on any type of riser because the legs of my bed are wooden, and about 4 inches long. These risers were perfect! Also, don't forget the poles underneath your mattress for King size beds--I ordered two boxes of 8, thinking I'd be able to put 3 risers under each leg, plus the pole underneath. Well I had 3 poles underneath, not just one.
We needed to raise our bed up just 2 inches. These one inch bed risers did the job. They are made of a durable plastic that stack and stay together.
I found that even double stacked, they didn't raise the bed high enough to slide the flat storage containers under the bed. It's really only like having in 1.25 inches using two because they sink into the carpet and carpet pad. Thought about buying a second set to get it higher, but then it's $9 a leg to get only 3.25 inches more space. Ordering a 5.5 inch riser set for about $5 a leg. Will find a purpose for this shorter set.
We purchased this set because the bed we wanted to use them on has very thick, square legs, measuring about 4" across. Its one half of a bunk bed set, and most risers were too small. This set was easy to put under the legs, because the bed did not have to be lifted super-high just to get them under (like other sets we tried) and there were enough in the box to stack them 2 pieces under each leg. We are very happy with this purchase!
Black Bed Risers - Set of 8 (Black) (1&#34; H x 4&#34; W x 4&#34; D). Bought two sets of these to raise my king bed another 2 inches off the ground. My wife hated the fact that the bed skirt was always on the ground. These work great. The only problem is that they do squeak a little when getting into and out of bed.
I only need 1 inch to put storage a container under the bed. These were perfect. Only needed one. Perfect yay I didn't need to remove the wheels. Really sturdy. Very happy with this purchase an price
Purchased 8 of these - 2 4-packs. Used to raise my fabulous new glass desk to a level so that I can use it as a standing desk. I love it - and another person in the office loved it too - so much that he purchased the same desk and Black Bed Risers to duplicate my efforts!
There isn't much to say. They stack solidly, but I'm not using them stacked. My Queen bed has 5 legs, so I have three left over.No problems after about a month of usage.
Answer: I've only stacked two for an added height of 2 inches, but I don't think there would be a problem stacking four for the height of 4 inches you're looking for. These are pretty sturdy risers.