Product: DIY Adult Masturbation Machine: How to have fun and save $400 at the same time.
A Do it Yourself guide to building an adult toy masturbation machine for both male and female use. These sell commercially for $300 to $600 or more. Build your own for about $100. 
 
These operate on 12 DC power for safety. Two versions in one document to accommodate various skill levels and tool availability.

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