About this 3D model

This thing inspired by [120mm Fan grill - RepRap style by capitaenz](http://www.thingiverse.com/thing:26396). I made it a symmetric and customizable. ##Customizable parameters are: - External dimension and mounting holes distance. - Mounting holes shape and size (cylindrical or for conic head screw) - Number of "rings" in grill. - Wide of "rings" and rods. - Shape of "rings" (true ring or tear drop). - "Rings" smooth or segmented. - Central "ring" solid or has hole. All .stl examples are for 120 mm fan.