Spigot x threaded Schedule 80 fittings include one spigot (or street) end and one threaded end. Spigots connect to another fitting and require glue or adhesive for a tight seal. Female threads are on the inside of a fitting. Male threads are on the outside of a fitting and screw into the female threads. Threaded connections use PTFE tape to secure seal. Schedule 80 fittings have thicker walls than Schedule 40, but not as thick as Schedule 100.