For sale here is US Post Korean War / Vietnam War M1 Helmet & Liner.  The chinstrap and inside of the shell are named to Donald R. Newberry.  The shell is a rear seam swivel bale.  The shell appears to have an overpaint.  The paint shows wear and minor scuffing.  The chin straps are clip on type with green painted clips from the Korean War Era.  The shell appears to be heat stamped I 1043.  The Firestone M1C jump liner is in excellent condition with a heavy texture paint.  This is a Vietnam War era Liner that appears to be dated 1968.  Unfortunately, the liner is missing the nape, chinstrap, and sweatband.  This is a great set that is worthy of research!