I purchased this new around January 2025, but it doesn't fit my baby's crib, so I'm selling it. GUSUMIN Anti-Roll Over & Face-Down Prevention Swaddle Belt for Babies [Compatible with Futons and Beds] When using with a futon, be sure to use a firm cotton-filled mattress. [Easy-to-Attach Single-Strap Belt] Simply insert the belt into the sheet to attach. [Usable Year-Round] Made of fabric, so it can be used regardless of the season. (When using in winter, autumn, or spring, adjust the room temperature instead of dressing the baby in thick clothes.) [Secured in Two Places] Secures the baby from two points: around the abdomen and under the crotch. Set Contents: Single-strap belt, dedicated sheet, instruction manual *Please refrain from using in conjunction with a sleep sack or covering with a blanket. If wearing a sleep sack, the belt may be more difficult to secure than usual because of the extra layers. If you are going to wear a sleep sack and then put the belt on, depending on the thickness of the sleep sack fabric, heat may build up. For comfortable sleep, please adjust the room temperature instead of using a sleep sack.