Timesulin is a replacement cap for insulin pens with a built-in timer that helps ease the daily anxiety and frustration that people with diabetes feel when trying to remember whether or not they’ve taken their insulin injection. It turns any major insulin pen into a ‘smart pen’ that shows how long it’s been since the last injection was administered, easing the anxiety that people with diabetes feel when they worry about the consequences of a forgotten or accidental double dose. Timesulin works with all the major insulin pen brands, requires no change in habit, is affordable and simple enough for anyone to use as it requires no programming or setup. As each cap’s built-in battery lasts for at least a year, the cap is reusable.