Firefighter Wedge

This thing was made with Tinkercad, but you can design your own in the Customizer: http://www.thingiverse.com/thing:93859

We use wedges like these to block open doors like a doorstop or at the hinge. Two wedges can be pushed together inside the frame of a sprinkler head to shut off the (copious) flow of water. Not sure if ABS is up to the stresses of closing a sprinkler head - I guess I will have to test. Print it in a bright color so that you don't lose it on the fireground.

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