HES RF5210 Tech Tips Smoke seals and door silencers serve their purpose, but can cause a preload issue and maybe a call back to the jobsite for an inoperative strike, or extra time trying to diagnose a rough engagement or release complaint. In some instances, the fix may involve drastic measures such as a new cutout, but not with the RF5210 hybrid electric strike. The RF5210 series keeper can be horizontally adjusted by loosening the two screws that attach the strike body to the face plate, and fine tuning placement to accommodate for whatever may be causing the issue. This will ensure the job is done right the first time. To learn more about this hybrid electric strike, please visit the 5200 product page.