FeiyuTech Kica Percussive Massager with 4 interchangeable ball heads to focus on many different muscles and joints. Despite its lightweight build, Kica packs a punch achieving up to 3800rpm. Full body constructed of aircraft grade aluminum for premium fit and finish. Smart Idle Mode: Kica will only increase speed when pressure is applied. Built in 2200mAh high density battery. 18 hours of battery life.