The Lehigh Valley IronPigs Theme Night Yellow 39THIRTY M-Crown Stretch Fit Cap features an embroidered Lehigh Valley Rubber Duckies theme night logo at the front panels with a matching MiLB Batterman logo at the rear, an orange visor, and a gray undervisor.

Inspired by the team's annual charity "Duck Night", in which fans participate in the "Chuck-a-Duck" fundraiser after the game.