Here is a sweet long sleeve sweater by Bel-Mor Knitwear. It's machine washable, so most likely acrylic or an acrylic blend. White fabric with vee neck. Nothing fancy about this one. Just a timeless, classic beauty. Warm, soft, comfy and in amazing shape! Here are the measurements. (refer to the last pic above to see how I measure shirts)

Chest (armpit to armpit) 20"
Shoulder to end of sleeve (including cuff) 24"
Length 24"

This item is sold from a vintage boutique in Roanoke, VA.