Some articles on whammers:

Slammer Whammers - Product
... The standard Slammer Whammers product was a blister pack containing 24 milkcaps and 2 slammers ... released various sets of milkcaps under the Slammer Whammers name, for example Biker Bugs, Wise Guys, Skull Squad and Wild Things ... There were 288 slammer whammers to collect ...