Below is the size chart for the Original Arm Trimmers:
Medium: 16" length x 5.25" width — recommended for arms up to 15"
Large: 18" length x 5.5" width — recommended for arms up to 17"
We do not make a size small at this time.
Below is the size chart for the Toned Arm Trimmers:
Small: 14" length x 5.25" width — recommended for arms up to 12"
Medium: 16" length x 5.25" width — recommended for arms up to 14"
Large: 18" length x 5.25" width — recommended for arms up to 16"