This is a full box of 18 Morley Yellow fiber tees.
Morley Yellow Tees were covered under a patent issued March 10, 1925, as stated on the box. According to their ad in the June 1927 issue of Golf Illustrated, each Yellow tee was "die molded, made of fibre and will not damage the lawn mower." Plus they would also improve your game by "registering on the bottom of the club how the ball is hit."