O RING SUIT TYPE 50 SPIGOT (THIN)
This is the sealing O Ring for the end of the Type50 Spigot Part# RGPRSFPNSK.
See the images for clarification of the end of the spigot to ensure you order the correct part.
NOTE the section where the O Ring sits in is not recessed. You may also check Part# RGPRSF1T50KORING as you may have a spigot part# RGPRSF1T50K, and if you check out the images you can see which one you have so you can order the correct sealing O Ring.