This 7.5 inch plaque was developed by the MGS Mfg. Group and is an educational tool used
to support the design, engineering, and manufacture of plastic injection molded parts. Mouse
and click the above plaque or buttons below to read detailed descriptions of each feature.

Rib Size and Boss Combinations
Ribs are raised features of a molded part designed to add strength, facilitate alignment during assembly and or can be functional as part geometry. Ribs are typically long and narrow and can vary in size and shape.

Ejector bosses are raised areas of part geometry where an ejector pin pushes on the molded part to release it from the mold. They are most often round in shape.

Together these two features also add structural integrity to part geometry. The combinations of size and width offer different looks and degrees of strength.