What is Fr in size measurement?
FR Size. What does FR size mean? FR or FG (short for 'French Gauge') refers to the diameter or thickness of the tubes. Every 0.33 millimeter (mm) of thickness /diameter, measured on outer walls contributes 1 FR.Also know, what is bigger 14 FR or 16 FR?14 Fr. 4.7 mm 0.185 in. 16 Fr. 7.4 mm ...