The Underwood barrel is dated "7-43". Fitted with the early style type 1 narrow barrel band marked "UI", fixed blade front and late style adjustable stamped rear sights, high wood pistol grip stock with a 2 rivet handguard, flat top bolt, checkered push button safety, and a milled trigger group. The sling cutout on the buttstock is stamped "TRIMBLE" with an oval cut oiler slot. Fitted with a tan canvas sling. The carbine includes an OD green "U.S." marked canvas carrying case. Author Larry Ruth states in his book "War Baby" that "E" prefixed serial numbers have been observed and may indicate either an experimental or presentation model.