The ring can be enhanced with defensive stats at Mobilising Armies for 106,000 Rewards Credits. Talk to War-chief Reeves on the second floor of the A.R.M.S. Tower to convert it to a ring of charos (a)(i).
If the ring is lost it can be pickpocketed from Doctor Fenkenstrain in his castle. The ring's activation is permanent, so when you reclaim the ring it will be in the activated form.
The ring's power to manipulate or fool the weak-minded has many potential benefits. While wearing the ring, if you are talking to an NPC and a "(Charm)" appears next to a conversation option, the ring's power will allow you to gain some sort of advantage. Below are a list of benefits you can enjoy.