Dynasty Hot Tub Pillows

This part is a Oval or Rounded Shape Dynasty Hot Tub Pillow for a Neck Seat, 1139, Black.   It is about 11" long and 4 5/8" Wide it has 2 tabs on the back that are about 6" apart.   It could have 1139 or 1139 B-1, 1139 B2, 1139 B3...