This Sea & Sea o-ring set is for the YS-120TTL Duo strobe. O-rings for a Nikonos 5 pin sync cord is included. The o-ring resembling a thick rubber band is designed to establish a watertight seal when going underwater.
Manufactured to precision tolerances required to hold a pressure seal on your housing and made of elastomeric material, it provides the means by which a watertight seal is formed.
UPC: 752221184303