Part number

101221 Nail

Holds the back panel on: 3 to square it, then 27 all round, into the back edges of the sides, the top and the bottom.

Used in

IKEA MALM chest of 3 drawers: 30 in the box, steps 19, 20, 21, 22

Missing one? Ask the store or its customer service for spare part 101221, and name the product it is for.