Hon&Guan 4 Inch Adjustable Air Vent Covers 100mm Ceiling Vent Indoor Vent Covers for Walls Closeable Round Ventilation Cover for Caravans, Cooling and Ventilation Systems

Used to replace extractor front. Good fit and adjustable to allow more airflow

I got this to replace a vent cover that looked old and yellowed and because it had louvres it collected dust and always looked grubby. This looks good (not brilliant white, more chalk white), is easy to fit, and the fins allow you to rotate it in and they pop out in the roof cavity holding the vent firmly in place without the need to use screws. You can unscrew the central part of the vent to vary the air gap. Great value for money, decent quality. I’m happy.

Easy to fit, just fold the fins in and push it in. If you twist it as you put it in it grips the plasterboard a bit more but might want some dabs of silicone to hold it a bit better. Diffuses the air to help reduce noise and can adjust the opening by twisting the middle circle. I agree with others that it doesn't look pure white. I think because it's not glossy compared to most white surfaces in a bathroom.

Good adjustable Air Vent cover, the only problem I had ( which I didnt solve) was how you seperated the parts in order to fix to the ceiling with the screws provided, I found it impossible to seperate , so mine is only held by the tesion onto the ducting. The instructions dont indicate or mention the seperation

These are ok quality wise but the diameter of the fitting is slightly too small to fit snuggly in 100mm duct so it leaves an air gap. Fine if you are using flexible duct though