Accutrim 1240 Series (RJ26 Style) Accutrim™ 1240 Series (RJ26 Style) ultra high precision Bulk Metal® Foil resistors offering proven reliability and excellent stability under different environmental conditions. The Accutrim™ 1240 Square trimming potentiometers are designed to meet or exceed the requirements of MIL-PRF-39035, Char. H with a smooth and unidirectional output. The 1240 Series have a virtually back lash-free adjustment mechanism, enabling them to be set both quickly and accurately whilst retaining the setting precisely on target.