The Geissele Super Select-Fire (SSF®) Trigger is a select-fire combat trigger that Geissele Automatics developed for the U.S. Special Operations Community. The SSF is a non-adjustable combat style two-stage trigger that is available in 4.5lb. and 5.5lb. configurations. In semi-automatic mode, the SSF is a precision two-stage trigger that allows precise and accurate trigger control. In fully-automatic mode, the SSF is a single-stage trigger with a smooth, continuous trigger pull and abrupt hammer release. The SSF is safety certified by Crane Naval Surface Warfare Center. NSN# 1005-01-618-8104 All NFA rules apply to the sale of the SSF trigger.