I just got the sheet and I have no desire to put on the mattress Fabimax co-sleeping as I read in other reviews. The packaging also stipulates that the sheet is for mattresses of 69 x 39 cm or 90 x 55 cm (which are the dimensions of the mattress with the addition fabimax). Just make sure to position it but I have not had too shot. I put 4 stars because the fabric is a little late, but it is sweet. See after wash and wear what happens.