These MF 850 Ball Valves have NPS straight (aka parallel) threads at each end, and are designed to be fitted with straight thread thru-hull or pipe fittings.
Straight threads are not "self-sealing". You must use pipe joint compound, thread seal compounds, or "Teflon(R) tape" to seal the threads when making connections.

These valves are made of exceptionally strong, fiberglass-reinforced Marelon(R). Marelon is both electrically and chemically inactive - making for easy installation, very low maintenance, and long service life for the end user, without the worry of possible corrosion over time. It is very light weight, has exceptional UV resistance, and will not freeze or become brittle with age.
Marelon exceeds ISO standards, is approved by the ABYC, and passes the same stringent Marine UL tests as bronze.

o Lightweight, yet extremely strong injection-molded parts
o For use above or below the waterline
o NPS parrallel (straight) threads
o Completely free from electrolysis or reaction to any metals - no electrical bonding required
o Completely free from any corrosion
o Minimal maintenance requirements - requires periodic lubrication
o Accepts adhesives and coatings (bottom paint) easily
o Can be used on aluminum, steel, wood, or fiberglass hulls
o Can be used with metal fittings
o Long term reliability