This red shirt, made by Pendleton, is 100% wool.
The shirt was seen on Ebay: https://www.ebay.co.uk/itm/236318343483. Photo credit AllThingsGirlyByNona. Seller’s description: ‘Vintage Pendleton Shirt Mens XL MacPherson Red Tartan Wool Plaid Flannel USA 70s. Condition: Gently worn, no visible flaws. Buttons all present, fabric in excellent condition with bright colors and soft wool texture. Brand: Pendleton. Material: 100% Pure Virgin Wool. Color/Pattern: MacPherson Red Tartan Plaid – vibrant mix of red, navy blue, green, and yellow. Features: Authentic MacPherson Red Tartan tag, classic button front, two chest flap pockets, button cuffs, pointed collar, made in USA. Size: XL (Mens) – measured approx 25″ pit-to-pit, 30″ back length. Era: Vintage 1970s (blue/gold label, made in Portland, Oregon)’.
Threads of Belonging 