Piercing on LetMeJizz
The assumption is a couple of nipple rings, but the real range runs from a single navel stud to clit hoods and pierced labia that catch the light in close-ups. Plenty of it is amateur metal on real bodies rather than studio-styled props, the hardware adding a glint to the spots the camera already wants to linger on.
311 piercing videos here, all HD and all free. New ones go up daily, so check back if you don't find your scene first time around.