THIS IS AN INCREDIBLY RARE HAMILTON 642 ALARM MEN'S WATCH, MADE IN THE 1960'S. THE MOVEMENT IS THE VULCAIN CRICKET BUT RELABELED FOR HAMILTON. IT WORKS WELL AND THE MOVEMENT IS CLEAN. THERE ARE TWO LAYERED CASE BACKS AND THE TOP ONE IS A LITTLE DENTED BUT I BELIEVE THIS CAN EASILY BE HAMMERED OUT. IT COULD USE A GOOD CLEANING, I DIDNT WANT TO HAVE ANY WORK DONE ON IT. I'VE SEEN THIS WATCH FOR SALE ONLY IN THE ROUND CASE STYLE, THIS CASE IS MORE OVAL/SQUARE HEAVY AND INDEED MORE RARE. A GREAT EXAMPLE OF THIS ULTRA RARE HAMILTON ALARM WATCH.