This one-sided Bulkhead is tank mountable with a flange. It is available in Nylon, Black Nylon, Polypropylene, HDPE and PVDF. UNF thread sizes are: 5/16-24, 10-32 and 1/4-28. The NPS sizes are 1/8” and 1/4″. Barb sizes are: 1/16”, 1/8”, 5/32”, 3/16” and 1/4″. (order as NN, BN, PP, HDPE, PVDF) O-Rings available.