ROFU 10318 16” Door Cord, 5/16” Inside Diameter

A door cord is the flexible loop that carries low voltage wiring from the frame across the gap into the door leaf, so power and signal can reach hardware mounted in the door (electric locks, exit device electrification, door position contacts) without the conductors being pinched or flexed bare every time the door swings. The ROFU 10318 is a 16 inch cord with a 5/16 inch inside diameter, so it is the wire-protection path, not the wire termination itself.

The ROFU 10318 gives 16 inches of loop between the frame-side and door-side ends. That covers a normal transfer near the hinge edge, where the cord only has to bridge a few inches of gap and absorb the arc of the swing. If your junction box on the frame sits well away from the hinge side, or the wire has to reach across to the lock stile inside the door, measure the actual run first, including the slack the loop needs at full swing, before committing to this length.

The 5/16 inch inside diameter is the usable bore, and that's the number to size your bundle against. Add up the outside diameter of every cable you plan to pull (lock power, request-to-exit, door position switch, card reader home run if it's door-mounted) and keep the bundle comfortably under 5/16 inch so the wires can move inside the cord rather than binding. If the bundle fills the bore, the cord flexes the conductors instead of sliding around them, which is what breaks wires over time.

Treat it as the cord assembly only. The conductors you run through it are specified by the lock, strike or exit device you are powering, so the gauge and conductor count come from that hardware's requirements, not from the cord. Order your low voltage cable separately and size it against the 5/16 inch bore.

Two different install approaches. A surface door cord like the ROFU 10318 mounts on the face of the frame and door and is the fast retrofit: no mortising, no removing the door, and the wiring stays accessible if you ever need to pull an extra conductor through the 5/16 inch bore. A concealed transfer or electrified hinge hides the wiring entirely and is what a spec will usually call for on a new fire rated or high-visibility opening, but it requires the door and frame to be prepped for it. If you're adding an electric lock to doors that are already hung, the cord is the practical choice.

It mounts on the secure side of the opening, near the hinge edge, with one end anchored to the frame and the other to the door face. Keeping it at the hinge edge is what limits how far the loop has to travel as the door swings; mounted out toward the lock stile, a 16 inch cord will be worked far harder every cycle and the conductors inside will fatigue sooner.

Yes, provided the combined bundle fits the 5/16 inch inside diameter with room to move. Running power and monitoring through a single cord is common on access control openings. What you should not do is stuff the bore solid: leave slack so the cable slides rather than bends at a fixed point, and if you expect to add devices later, pull a spare pair now while the cord is open.

It's a commercial door hardware item. Typical uses are electrified openings in offices, schools, healthcare and multi-family buildings where an electric strike, electrified lock or exit device sits in the door leaf and needs a protected wire transfer from the frame.