Replace a cracked, broken, or missing steam knob on your Gaggia espresso machine with this genuine OEM steam tap knob (part 421941022781). Features a D-shaped pin hole (6 x 4.6mm) for a secure, wobble-free fit across multiple Gaggia Classic generations. Part Details Part number: 421941022781 Official Gaggia OEM spare part D-shaped pin hole: 6mm x 4.6mm Compatible with Gaggia Classic V1 (pre-2015) and V3 (2019+) Also fits: Gaggia Coffee DeLuxe, Baby, Baby models, and Coffee 97 Features Genuine Gaggia OEM — not an aftermarket copy Secure D-shaped fitment prevents knob slipping during use Restores smooth, precise steam flow control Direct press-fit replacement — no special tools required Frequently Asked Questions Which Gaggia models use steam knob 421941022781? This knob fits the Gaggia Classic V1 (pre-2015), Gaggia Classic V3 (2019 and later), Gaggia Coffee DeLuxe, Gaggia Baby, and Gaggia Coffee 97. The key identifier is the D-shaped pin hole measuring 6mm x 4.6mm — check your existing knob before ordering if unsure. How do I know if my Gaggia steam knob needs replacing? Common signs include a cracked or broken knob body, a knob that spins freely without engaging the valve, or one that has snapped off entirely. A damaged knob makes it impossible to control steam flow safely and should be replaced promptly. How do I replace the steam knob on a Gaggia Classic? Ensure the machine is off and fully cooled. Pull or unscrew the old knob from the steam valve shaft. Align the D-shaped hole of the new knob with the flat side of the shaft and press firmly until seated. Test the knob turns smoothly and engages the steam valve before use.