I have built in shelves in my garage. Would these slide out shelves fit within the existing shelves?
My next project for the garage is to add insulation and installing new drywall and polishing the floor like Mr. Incredible posted.
No, they are stand alone drawers, like filing cabinets but typically used in machine shops or similar situations where you have to organize lots of small metal parts. Screws, drill bits, end mills etc. This is mostly what you see on the used market. If ordering new they'll make you whatever configuration you can dream up.
retrofitting drawers to your shelves is very possible on a DIY level from making it all from scratch to various degrees of having a pro do it and you install.
I'd like to build something similar to an FRS someday. No wasted space there.
http://www.armyproperty.com/Equipment-Info/M7-FRS.htm
That is badass. I am purposely not looking those up on auction sites.