This is a very nice all original German KK43 semi auto rifle that was manufactured in 1944 at the Walther Arsenal. Mechanically this rifle is in excellent working order and is a great shooter.  This rifle is not import marked and is most likely a WWII bringback.  This is a rare “panel cut” receiver only seen on a few Walther rifles within this block.  This rifle would be very hard to upgrade in your collection!