Walking I use two Gatorade 600ml bottles . One with water and the other with a home made electrolyte powder.
I wash the bottles after every walk.
Last time by mistake I tossed the lid of the two in the rubbish.
So , as I do when I need a new bottle, I was looking for discarded Gatorade bottles to replace those tops.
Today I remembered to do so and just a few minutes from home spotted a twist top on a soft drink bottle that looked the right size.
Took it home and found out that it does indeed fit my bottles. You need to remove the "ring" that remains after you twist the original top off.
Now I can drink using one hand only...