Botox is measured in units, and the number of units needed varies by area, muscle strength

https://www.google.com/maps/d/embed?mid=1ZiMC_L1MWl7g1PMztb3CWG-slr0bkrY&ehbc=2E312F&noprof=1

Botox is measured in units, and the number of units needed varies by area, muscle strength, and desired intensity of softening.