Each pin is wrapped to protect the fiber-optics from bending or breaking. They fit 3/16" sight slots. Per each. Dot sizes: .019", .029". Colors: Red, Green.
I wanted a smaller sight pin the took up less of the target and this works perfect. And being fairly cheap I changed all my pins to these ones and it was still cheaper than buying a sight that already had them.
i have a 3 pin sight already, but i bought these for longer shots. the smaller diameter helped me to focus on the longer 50-60 yard shots. very easy to install etc. much cheaper than the cost of a new sight upgrade.