It is a cushion for a guitar case,
One of my boys Jonno came to me and asked for something to allow him to put his electric guitar into his accoustic case. This is what we ended up with. What i did was trace the outside of the case onto some yummy fabric (a second hand wool and cashmere mans coat) cut, sewed and stuffed then added thick crochet cotton for the dimpling. A great project for the afternoon. (he now owes me a second hand coat).