A deceptively simple contrivance with an ultra-bright LED that contains its own flash timing circuit.
The LED only flashes once a second (1 Hz), which is well outside the danger range for triggering photoepilepsy (5 to 26 Hz). This fetching pin can be worn by anyone as an eye-catching accessory.
It is powered by inserting a CR1632 battery into its holder, with the “bump” (negative) side inward towards the front. To de-activate the LED, simply take out the battery.
This item is sold for the low price of $12 USD, plus shipping.