Jarvis Pym's original ring containing the sodium calcium chloride.
Finger ring with a secret compartment.
Used by Maxwell Smart and KAOS's self-styled "mad pharmacist" Jarvis Pym.
When Smart and 99 thwart Pym's plans he declares that he has nothing left to live for and proposes to do away with himself by taking sodium calcium chloride, the second most deadly poison in the world (after artificial sweetener), hidden in his ring.
Max counters by revealing the anti-sodium calcium chloride hidden in his own ring with which Pym would be revived.
Pym then reveals a second ring containing pro-anti-sodium calcium chloride with which would be "permanently disposed of".
However, Max also has a second ring, this one containing anti-pro-anti-sodium calcium chloride. As 99 explains to Pym, "If you take sodium calcium chloride and Max brings you back to life with anti-sodium calcium chloride and you decide to destroy yourself again with pro-anti-sodium calcium chloride, Max will bring you back to life again with anti-pro-anti-sodium calcium chloride."
At this point both are out of rings and Pym is thus prevented from committing suicide but is subsequently shot when Max accidently fires his gun, the bullet ironically ricocheting from Pym's ring into his shoulder.
[Episode #124: "Is This Trip Necessary?"]