The HES 8000 Series is a compact, high-performance electric strike featuring a unique concealed design for use with cylindrical locksets. No cutting on the frame is required. Simply remove the existing strike plate, adjust the vertical alignment feature to the latchbolt centerline, and install. Its strength is derived from a unique keeper pin locking design, enabling the 8000 to exceed the ratings of the frame, door and locking hardware. This field selectable fail secure/fail safe unit is easy to install and accommodates latchbolts up to 5/8" throw.