High density 40D sponge material provides strong resilience and comfort, and it does not collapse. Fills the gap between the mattress and the headboard, wall, or footboard, and prevents pillows, pets, and toys from slipping off the bed. Easy to cut to any length or angle. Ships under compression and will fully expand after 24 to 48 hours. Wide application: sponge strips offer comfort and support and are easy to use. Suitable for dormitories, bed seams, and patchwork beds. Usage scenarios - Master bed or guest bed: fill the space between the mattress and the headboard to create a seamless edge and keep pillows in place. - Dormitories or patchwork beds: use along bed seams to stabilize bedding and reduce gaps in irregular bed configurations. - Homes with pets or children: place along the edge to prevent toys and small pets from tumbling off the bed.