I saw an earlier recommendation and went to Amazon. They have pages of them, differentiated by color and style, which made me realize they are a commodity, in common use among a particular large population of at risk people. They’re not covered by health insurance, so there’s actual competition. Look at the ratings and use your usual yardsticks to pick ones that people who have bought before find to be reliable and useable.
I saw an earlier recommendation and went to Amazon. They have pages of them, differentiated by color and style, which made me realize they are a commodity, in common use among a particular large population of at risk people. They’re not covered by health insurance, so there’s actual competition. Look at the ratings and use your usual yardsticks to pick ones that people who have bought before find to be reliable and useable.