New Doorzipper Makes Standard Home and Business Entry Doors Impervious to Forced Entry

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Most entry doors offer little resistance to kicking, much less ramming force, but the new American made Doorzipper™ renders a door so impervious that the hinge side has to be reinforced to match … or become the weakest link!!

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The stories abound about the rise in forced entry … scrap metal and gold prices are up, more people are out of work .. it's a recipe for increased business and residential break-ins.

Enter Stan Demster of KJD Services in Shawnee, KS. Stan is a fifth generation Kansan and holds dozens of patents … he has worked with everyone from Honeywell and the FAA to York International and Hasbro (on the Light Saber for Star Wars). The prolific inventor has engineered and patented yet another solution to an age old problem.

Stan's home and those of several of his neighbors had been forcibly broken into. While the intrusion angered Stan, the engineer in him could not just let him reinstall the deadbolt that failed … he had to have something better.

While Stan perused the damage to his door frame caused by the brute force applied to the deadbolt area, he realized that the ramming device used by the thieves had delivered a tremendous amount of ft/lbs to a very small area causing structural failure of the surrounding wood and the hollow tube than in essence was supposed to be the core strength of the deadbolt.

As with all great ideas, simplicity ruled the day … Stan came up with a straightforward way to spread the energy of a forced entry attempt across so many points that each one was totally ineffectual. The Doorzipper was borne of equal parts necessity, ingenuity and physics.

An installed Doorzipper engages 24 interlocking stainless steel tabs along the edge of any door with the twist of a key or latch, just like a deadbolt. Invisible when the door is closed, this silent sentry is so effective that the Shawnee, KS fire department has asked that Stan also produce a sticker to alert them when one is installed so they know to just use a chainsaw to cut through the wall so as not to waste time trying to force open the door!

Twenty four tabs means that even if one could (and you can't) exert 1,600 ft/lb of energy at a door equipped with a Doorzipper, each interlocking tab set would only receive about 66.6 ft/lbs of force … hardly enough to knock in even the least expensive big-box store door.

Windowzipper is the next iteration of Mr. Demster's invention and assuming the use of shatter resistant glass, a window and Doorzipper equipped house or business in effect becomes a giant "Panic Room" sealing out any and all uninvited "guests". With one of the worst economies in history, Stan elected to start a small business to provide jobs to people in the Kansas City area. He is selling a locking system that is "Made in USA" (The big name lock companies are all owned by foreign holding companies that buy parts from India and China, KJD buys theirs in KC and the surrounding area).

Doorzipper will be hiring up to 30 people in manufacturing, administrative and sales. For additional information on the Doorzipper, contact Stan Demster at KJD Services in Shawnee, KS or visit

About KJD Services:
KJD Services Inc. was established in 1987 and is a privately owned research and development company that specializes in solution engineering. Their newest solution is the Doorzipper.

The Doorzipper is a "'system engineered solution", that is intended to replace the weak single point deadbolts that have been found on most household doors for decades. Doorzipper is a strong multi-point tab locking device that is specifically designed to strengthen and protect the door and door jamb from physical failure. The door is effectively woven to the frame making forced entry all but impossible.


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Paul Evans
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