You need 1/4 so that the 1/16-deep threads will bite into the 1/4 mounting holes. The manual with the door is mistaken about that and about removing the frame members to level, plumb, mark & drill and mount the door, See the video for partly updated and improved installation instructions. Evidently people are having so much difficulty that the door as now being squared and clamped like any prehung door . . . because squaring and plumb-ing a door piece by piece is work with more experience and skill than typical diy householders.
The one way screws are meant to be driven clockwise/tighten only to prevent a door's rapid removal/break-in using a cordless driver/drill. All screws are current as well as present any time you see them, installed or otherwise. Any screw can only be removed only if it is presently installed; but any screw driver--except the tool you are asking about-can turn a screwhead CCW to loosen the screw. Because an anti-ccw screw has no slot edge for forcing the screw to rotate ccw, then no driver too including "this" one can uninstall on
Thank you for your interest in our Su Casa Security Door. If it’s only temporary you can use #10 X 3- 1/2” drywall screws. I hope this information is helpful for you.
Thank you for your interest in our 4 inch one-way screws. We suggest you speak with a mill work associate at your local Home Depot store for more information on availability and ordering. They can advise you as to which stores near you may stock these items. I hope this is helpful.
Thank you for your interest in our 4 inch one-way screws. The heads of the screws are either white or black depending on which package you buy. The threads of the screws are always black as they are not meant to be seen since they are screwed into the wall/door frame. I hope this information is helpful.