Youth Boston Celtics Pajama Pant Boys Sleep Bottoms. These PJ sleep pants are made of 100% Polyester for a softer feel and feature the Boston logo as a repeating all over print on top of a Celtics team color pant. These pants feature a drawstring waist and are great for lounging around the house on those cold winter mornings! Your little BOS Celtics fan will love wearing this around the house on game day! Officially licensed Boston Celtics fan gear.