Pendleton Canterbury flannel shirt.
Brushed pima cotton/merino wool blend in red/blue/gray plaid.
Button down collar & chest pocket (machine wash/hang dry).

Good condition - no holes or damage, does have two ink-like marks as shown (pocket & sleeve), not too noticeable, blend in fairly well among the busy pattern.

Tagged large. Measurements in inches:
pit to pit 23.5
waist 22.75
shoulders 19.5
sleeves (from shoulder to cuff) 24
rear length (excluding collar) 30.75