The first transistorized computer made by IBM was the IBM 7030 or STRETCH. The first of these was installed at Los Alamos in 1961. The following year, a customized version of the STRETCH known as the IBM 7950 or Harvest went to the National Security Agency at Ft. George Meade, Maryland. It ran there until 1976. The Harvest included a system of six drives which handled data on magnetic tape stored on cartridges. This was known as the TRACTOR tape system or IBM 7955. This is part of the TRACTOR system. It is a frame designated by D.