In 1967 I was stationed at Ft Carson CO...the Coors beer was shipped only to the surrounding states of CO.. And the can had a dimple on the top which had to be pressed before using the opening clip..anyone know why or what the reason was. ? About a month after I was out I had a friend send me a six pack to the east coast...yuk....certainly not made for travel at that time..
Are you talking about Coors' "Press Tab" can lids? They were an anti-litter replacement for the old "Pull Tab" cans, but 1967 is way too early for them - mid-1970s would be around the correct time. A few other brewers used and later dropped them, as well (Genesee being another). See my previous post on the topic. . Also, by the mid-60s, Coors was in a number of states west of the Mississippi (not just those neighboring Colorado), including California, where it was already the #1 brand in '67 with 20% of the market.
This ad and similar ones appeared in Coors' marketing region (Kansas to Calif., Idaho to New Mexico) in the period 1974-75, but mentions of the lid design started as early as 1972-3 (maybe test markets?). An AP story in April, 1978 noted:
That is it!...i had forgotten..ibknew it released pressure..but did not recall the downward motion for the tab...