Radius Solid Wood - handmade - Muntins Muntins = our nerd word for those little dividers between the panes of glass! Lights = the individual openings/glass. The mullion is the part which separates the individual assemblies, whereas the muntin is the divider which separates the individual pieces of glass. So in the trade language we make true divided light, using historically accurate joinery with full tenons in your sash frame. Mortise and tenon joints do not rely on glue or fasteners, that's wh