Avon Protection FM50/C50 Face Sizing Tool White. The 50 Series sizing tool allows the wearer of a C50 or FM50 to determine their size between the three available sizes: Small Medium and Large. For reference: On average 70percent of wearers fall within the Medium size range. Specifications for Avon Protection FM50/C50 Face Sizing Tool: Manufacturer: Avon Protection Color: White Fabric/Material: ABS Package Contents: Avon Protection FM50/C50 Face Sizing Tool Avon Protection 71601-31: FM50/C50 Face Sizing Tool White