Midwest Engineering and Design

Sell plans for such items as underwater camcorder housings, 1 and 2 person submarines, hydrophones, ultralight aircraft, scuba tow scooters, and pulse induction metal detector.
http://www.angelfire.com/ks/diyplans/index.html - Detail
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Affordable Submersible Products

Plans for an underwater video camera housing, lights, and a waterproof keychain laser pointer by Gary Dagastine.
http://members.tripod.com/econosub/ - Detail
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Scuba Tow

Build it yourself diver propulsion vehicles (DPV) plans for the scuba tow and a one man submarine.
http://www.scubatow.com - Detail
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Scuba - do it yourself

Reinhard Kopka's site dedicated to homemade diving equipment and accessories. Plans range from lights and dive computer interfaces to diver propulsion vehicles and rebreathers.
http://insel.heim.at/malediven/350052/english.htm - Detail
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Lee Engineering

Plans for the 'Picture Toob' underwater camcorder housing developed by an engineer who enjoys water activities.
http://pw2.netcom.com/~awing/video.html - Detail
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Lunkercam

Plan to build underwater video camera.
http://www.mninter.net/~boardman/ - Detail
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Elfmun Underwater Products

Offers plans, parts, and kits to build underwater canister dive lights and video housings. Includes ordering information, price lists, and contact details.
http://www.scuba-lights.com/ - Detail
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