Hon&Guan 4 Inch Adjustable Air Vent Covers 100mm Ceiling Vent Indoor Vent for Walls Closeable Round Ventilation Cover for Caravans, Cooling and Ventilation Systems, No drilling

If you have a four inch hole that needs a white plastic vent in it then this is just the job. If your hole is bigger or smaller than four inches then it won't be much good.

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.

I got this to make a spray paint booth in my back bedroom. I liked the design and the fact that the inlet area was adjustable on a single screw thread. Its well made, tough and durable. For me it didn't need any fixings as it sort of screws into the opening with the three attached locking vanes expanding out behind it securing the vent to the opening. I am using it for a booth so the wall thickness is about 12mm. I do think it will work well on thicker walls but may need screws or bonding agent like No More Nails etc. For me, it was perfect for the job, looks great and pretty decent price.

great product well made and finished, simple fins that fold in when you turn the unit clockwise mean that its simple to install into the opening and grips well once in place. Centre cap screws in and out to adjust air flow

Undecided about the quality and effectiveness to seal fully. The wings that hold the Vengt in place, becomes a barrier to sealing the vent hose. Used Jubilee Clamp and Tape to ensure a good seal.