4055986618 Genuine Electrolux Universal Stove Knob 40mm Stainless, Single Knob UK-40S1 with Shaft Inserts for Gas and Electric Cooktops

One knob missing or cracked? Part 4055986618, also sold as UK-40S1, is a single 40mm universal control knob in a stainless finish, supplied by Electrolux. It's made to replace hotplate and gas burner knobs on a wide range of stoves and cooktops. Shaft inserts come with it to suit both 6mm D and 1/4 inch D shafts, so the one knob can be set up to match different controls.

When a gas burner or hotplate knob slips or breaks

Each knob turns either the simmerstat that sets hotplate heat or the gas valve that feeds a burner, and its pointer tells you where it's set. Knobs near the burners get baked by heat every day, so the plastic turns brittle and the socket that grips the shaft can split. Then the knob slips, wobbles or comes away in your hand, and it's hard to tell whether a control is really off. Because this is sold as a single knob, you can replace just the damaged one rather than buying a full set.

Part details

• Genuine Electrolux part number 4055986618
• Also sold as UK-40S1
• Single universal knob, 40mm diameter, 22.5mm high
• Stainless finish with a pointer marking
• Shaft inserts for 6mm D and 1/4 inch D shafts in flush, 10.5mm and 19.5mm lengths
• Black and red pointer inserts and gas ignition collars included

Setting up the knob

Turn the control to off and let the cooktop cool. Switch off at the wall, and on a gas cooktop close the gas isolation valve as well. Pull the old knob off and look at the shaft shape and how far it sticks out. Choose the matching insert, press it into the knob, then push the knob onto the shaft with the pointer at off. If a burner doesn't light normally afterwards, stop and call a licensed gas fitter.

Questions about this part

Which shaft insert should I use?

Match the insert to your shaft. The kit covers 6mm D and 1/4 inch D shafts, with flush, 10.5mm and 19.5mm long inserts. Choose the one that grips firmly and lets the knob sit close to the panel without rubbing on it.

Is this one knob or a full set?

It's a single knob with its own inserts and collars. Order one for each control you're replacing, so you only pay for the knobs that are actually damaged.