In our house 15 years ago, there was a simple thing without even a hook hook for a detachment just by the insertion port. What happens when the hose comes off the washing machine in the event of an earthquake? Imagine that you suddenly needed it and replaced it. As for the thing called a washing machine, please read the instruction manual and close the faucet except when it is in use. I do not expect such use in our house so I expect it from this stopper. I hope that time will not come. It is a specification that does not pass water unless the stopper works. To worry about forgetting it. It is a refreshing and unreliable thing.