Fits most head immobilizer bases these are very similar to our 10-011 replacement pillows for adults but smaller. This is necessary for infants due to their smaller size and is sold as a pair. The vinyl coating on foam provides an easy to clean surface. Features: Pediatric head immobilizer blocks Necessary for infants due to their smaller size Easy to clean and disinfect for reuse Highest grade of foam with vinyl coating Dimensions: 4.25 H x 4.25 W x 5.75 D Material(s): rubber