The name is striking and simple, and gives an immediate clue to its format. The Pentax 17 is a half-frame 35mm film camera. This means it shoots two images on a single 35mm frame, which measures 36 x 24mm. Halve the width, remove a millimetre to give each image some space, and you get [36/2 - 1 =] 17mm… More here.
Love the idea and the look. Not so much the price…