The Shark FlexStyle Curl-Defining Diffuser attaches to the Shark FlexStyle for fast, even drying from root to tip. To enable curl-perfection, our diffuser features retractable and extendable prongs. Retract prongs for shorter, finer hair and less heat on the scalp. Extend prongs for longer, thicker hair and for reaching and lifting at the root. Compatible with: HD430, HD430C, HD435, HD440, HD430REF, HD435REF, HD432PK