Inner diameter 3 cm, surrounded by flexible wings. Travel lock function, Charge indicator light, 6-8 hour initial charge, Up to 120 minutes of play on one charge 18cm/7.1” total length, Internal diameter: 3cm/1.8”. Designed and handcrafted in Germany. Free tester with $400 of Fun Factory purchase. Must be ordered in order to receive the tester. 1 tester per store per year. Brick & Mortar stores only.