Threaded Rings for VesselsThreaded Ring Set consists of one male thread and one female thread. Threaded ring sets are used to make vessels, jars, urns, etc while having metal threads to connect the lid and base. The stepped male ring gives you metal to metal meet up instead of wood to wood. The major diameter on both the male and female ring is knurled to help with glue adhesion. Made in USA We recommend BSI 30 min Epoxy for good strength.