Mess is an abbreviation of the German word entfernungsmesser, literally "distance meter", or rangefinder, indicates it has an uncoupled rangefinder. Mine was a 'pre-owned' and cost £17-10-00 (psd) in 1954 when I was 16 and the average wage was about £10 per week, not that I was earning that much as an apprentice.
I must have traded it in when I got a MPP Microcord II and I've looking for an example in reasonable condition and for sensible money for my collection for a number of years. These cameras usually go for well over £125 especially in Europe and the States. Imagine my delight at picking up a very clean example off E-Bay for under £45 that works!!!
The 524/16 was made between 1952 and '57 and fits in the Zeiss range between the Super Ikonta and the Nettar rangers. 12 shots on 120 film which made you think before you pressed the shutter especially with the cost of film and processing in the '50's. My original one had a f3.5 Novar lens as does my new one but there are rare examples with the f2 Tessar. I'm a happy bunny!