Imperial Inches
Total Length 8.7"
Usable Length 7.3"
Head Circumference 4.7"
Head Diameter 1.5"
Medial Ring Circumference 5.1"
Medial Ring Diameter 1.7"

Metric CM
Total Length 22cm
Usable Length 18.5cm
Head Circumference 12cm
Head Diameter 3.75cm
Medial Ring Circumference 13cm
Medial Ring Diameter 4.25cm