Cross leg block foam positioner - 16" L x 14" W x 10" H - w/ waterproof coating. Altra Care foam positioners come in multiple shapes and sizes. These MRI compatible positioners, with a non-skid coating, are ideal for patient positioning. They're patient-friendly (they're latex free and the foam provides comfortable medium firm support), but they're great not only for patients; the positioners are reusable and water-proof (they have a fluid-proof durable Altra-Care coating), disinfectable, and with no seams, wrinkles, or zippers, they're easy to clean.