This is a Vietnam-era Benrus Disposable Military Watch with manual-wind movement housed in an OD plastic case. Being a disposable watch, not many of them survived the war. Mil-spec for this watch is MIL-W-46374, making it the first series of field watches. Current field watches, like Stocker & Yale Sandy's, are made under MIL-W-46374F specification.

Back of the case reads as follows:

WRIST WATCH (NON MAINTABLE)
FEDERATION STOCK NO. 6645-952-3767
MFG. PART NO. 11K1185Q
CONT. NO. 25-69-C0011
DATE: DEC 1968
BENRUS WATCH CO
MIL-W-46374

The watch when I had acquired it was running very slow, so I had it cleaned and lubricated. It runs very well now, about +10 sec a day. Like other military field watches, it has a one-piece plastic case, so the movement can only be accessed by removing the crystal. The luminous markers on the dial still glows after exposure to light. Funny thing about it is that, unlike other military field watches, the number 12 on the dial glows too. The watch came with the original olive drab nylon band that looks as if it had seen some combat actions!

I plan on upgrading my collection of military field watches to military diver's watches, so I've decided to write this short review before it leaves my hand.