Weston Master III Universal Exposure Meter Model 737 / S141.3: 1956, USA and UK manufacture. Brushed steel cased USA meter (left), the rarer red dial UK model (centre) and standard glossy black enamelled model (right). Note that the American model (left) now uses A.S.A. film speed rating whilst the UK models retain Weston Speeds. With all three models now incorporating the Exposure Value (EV) scale the calculator dials on the two British models have been redesigned. The addition of the EV scale and the new dial design with its red variant are the only differences (on the UK model) between the Master III and the earlier Master II. The rest of the meter remains the same. An interesting detail on the US model (left) is the further addition of a scale for the Polaroid exposure values.
One option for fitted cases for this series of meters is shown here. The back section of this ever-ready case has a recessed compartment to house the invercone and filter for high light levels. The Master IV and subsequent Masters had a redesigned perspex invercone which was protected in a separate 'satchel' type leather case.
Not long ago, my friend David Paschke in Maine, USA found this curious item listed on Ebay. It's a printing block, much smaller than it looks with a print area of 3 x 4 cm and it is reckoned that these would have been distributed to dealers. With an inking pad to hand, the dealer could add the image of the (USA brushed silver finish) Master Model III to an advertising leaflet, business card, letterhead, sales receipt or whatever. My best impression from an ink pad is on the right. A print from the block in it's pristine condition in 1956 would certainly have been much cleaner.