These sheets are perfect for my son’s bunk bed! They are excellent quality, fit perfectly, and the zipper functions perfectly. Super easy for a 5 year old to zip up. I am so thankful to have found the solution to our bunk bed sheet problem. No frustration in the middle of the night in tangled sheets. I looked at several other brands online and this was the only set I found that was 100% cotton and seemed to be high quality instead of the “As Seen On TV” sort of stuff that was either polyester or fleece which is just not going to be comfortable or cool enough. I was absolutely delighted with the quality when I received them. Excellent fabric, nice weight that lays flat, and the fit is perfect for the mattress. I am just tickled with these sheets and will be recommending them to all my friends with kids. Even if you don’t have bunk beds, they would be great for just keeping kids in the bed and keeping the bed neat. Also much easier for kids to make their own beds with these. Very very happy with this product!