This article contains the FAQs for the HD400 Series Shark FlexStyle™ Air Styling & Drying System. This supports the following model numbers: HD400, HD400BK, HD400BKCCO, HD410, HD420, HD430, HD430C, HD430REF, HD432PK, HD432PL, HD435, HD435REF, HD440, HD440BK, HD440BKCCO, HD442BK, HD442BP, HD442OR, HD442PL, HD450TL, HD450TLC, HD454CO, HD442JB and HD463H.