Scarce Authentic US Army issued M4 60-87 MM Mortar Sight with original Graton & Knight Co # D29377 marked M14 leather case. The M4 Mortar Sight is a small, simple instrument utilizing a collimator/sighting scope instead of the elbow telescope used on the more advanced M64 and M67. From the Infantry Journal, 1942: The Sight M4 , provided with the 81mm mortar for laying in elevation and direction is likewise the standard sight for the 60mm mortar. The sight includes a collimator, elevating and lateral deflection mechamishms, and longitudinal and cross levels, asll supported by a bracket with a dovetailed base which fits in a slot in the mortar yoke and latches in place. The Sight M-4 is an accurate, ruggedly constructed instrument used to lay the mortar for direction and elevation. ORIGINAL & AUTHENTIC WW2 US ARMY ISSUED. EXCELLENT CONDITION.  This will not be around for long and are no longer released from the Govt.