For instances which should have individual shapes close to the load. A very fine grid - only 10 mm x 10 mm - allows tight contours.
All 30 cm x 30 cm inserts are superb for individual filling of usual board game boxes e.g. Star Wars X-Wing Miniatures Game, Star Wars: Armada, Zombicide, Descent.
Board game boxes have often square inner dimensions between 28 cm - 30 cm. So if the board game box is 28 cm wide, you have just to remove 2 rows of foam (each is 10 mm wide) and the foam tray fits perfect!