.GSTENCIL File Extension
File TypeOmniGraffle Stencil
What is a GSTENCIL file?
Vector graphics library used by OmniGraffle, a diagramming and sketching application; similar to a clipart library since it contains pre-made images, called stencils, that can be inserted into a diagram; saved in an XML format but encodes the image data as blocks of text.
GSTENCIL files allow OmniGraffle users to share stencils. You can install the stencils by double-clicking the GSTENCIL file.