The KH-8 Dual Mode, also known as Higherboy or Highboy, was a modified version of the KH-8 Gambit-3 reconnaissance satellite developed in the early 1970s as a contingency measure in case of delays with the KH-9 Hexagon satellite. Retaining the basic layout of the KH-8 Block 4 series, it consisted of a photographic payload section, satellite control section, and booster vehicle. Notable features included a strip camera coupled with an optical system with a focal length of 4.46 m, capable of capturing images with ground resolutions as fine as 0.1 meters. The Block 4 version offered dual platen capability, accommodating both 9-inch and 5-inch film, providing versatility for various imaging needs including experimental films, color film, and false-color infrared. Additionally, the Astro-Position Terrain Camera (APTC) included three cameras for terrain and stellar observation, aiding in attitude determination and navigation.