A trigger in binary manner employs two separate sears. Following the trigger is pulled and a shot is fired, the hammer recocks along with the disconnector arrests the hammer to prevent automatic fire (just like it does in semi-car mode). The BFSIII B&T-C1 is explicitly designed for the B&T APC9 https://gregoryzzywt.blogozz.com/32066059/binary-trigger-glock-no-further-a-mystery