This is a travel letter/word game that was given to members of the American Airlines Sky Club in 1971 as a form of advertising. It appears this was designed to be played to pass the time during long flights. Each packet contains a blue slider sheet with 10 square holes with corresponding top/bottom slits, plus 1 cardboard strip listing 24 categories, and 10 strips each containing all the letters of the alphabet (A-Z). The strips are designed to slide through the top & bottom slits, so that only 1 letter (or category) is visible through the square hole. The first player holds the slider sheet horizontally and selects a category. They slide the category strip vertically into the slider sheet until the chosen category is visible. Then, they mentally choose a word for the other players to guess. They slide 2 letter strips vertically into the slider, so that only the first and last letters are visible. The other players in clockwise order call out letters they believe will fit this word. Letters called that do NOT appear in the word score 1 point against the caller. Correct letters are positioned in the proper slots. When any player guesses the original word correctly, he wins 1 point and becomes the next word/category selector. The game ends when 1 player wins 10 points. Listed in American Games, #4213. 1971, Travel, Advertising, Ad game for Airline, Board game.