OK so here is the refrigeration service engineer booklet volume 14 #12 from December 1946 literally right after World War Two here's the fun part this is a total wealth of information on commercial refrigeration of this time this has advertisements from every major refrigeration parts maker that there is now that there was then for instance sporlan or alco they are all advertised through here this thing for the commercial refrigeration man is absolute fun going through looking at Mueller brass massive open drive air conditioning compressors ammonia systems alco thermostatic expansion valves at are of yesteryear that's for sure I don't know I really don't wanna sell this booklet but my wife ended up putting it in a pile to go so I'll offer it hopefully it stays with me this thing's cool sorry I'm reading it as I write this down but here you go it's brand new it's still in the package it was mailed in in 1946 and doesn't look like it was ever opened up or even read please take a look at the pictures and ask any questions thank you for looking