Tweak nipple suckers  another unique design from the Kink by Doc Johnson collection  create powerful natural suction for intense sensations and engorgement that traditional clips can't provide. With a simple squeeze  the Tweak set fits perfectly against the skin and creates a strong seal for hands-free fun - just attach to each nipple and watch them swell through the visually stimulating sheer black material. Kink by Doc Johnson is an exciting collaboration with Kink.com to create a collection of high-quality authentic fetish items suitable for long-term practitioners and new initiates alike. Soft Material Forms Comfortable Seal When Squeezed; Designed for Hands-Free Wear; Nipples Become Larger and More Sensitive; Phthalate-Free  Body-Safe. Total Length 1.75 (in) / 4.45 (cm) Width/Diameter 1 (in) Circumference 4 (in) / 10.16 (cm) Material TPE.