Thank you for your question.
I can understand wanting to know the size of the adapter to see if it will fit your faucet.
• If you have an aerator on your faucet, it will likely fit the adapter that comes with the washer. The new machine will come with the faucet coupling that will fit a lot of faucets and one adapter that will fit most faucets. But there are just too many different sizes to be able to tell you if it will fit.
• There are a number of different designs on faucet head aerators, the ones with outside thread and ones with inside thread of differing thread sizes.
• If when you install the washer, and if the adapter does not fit, I would suggest you take the washer coupling connection adapter and take the sink faucet aerator and take them both to the hardware/home center and you should be able to find the correct size to get the washer to connect to your sink.
• If you do not have an aerator on you sink faucet it may require a special fitting that you may have a handyman or a plumber install.
I have given you a picture of couple adapters below with there sizes.
I hope this will help with your