"the chain trick"

Acquire smoothest chain available.
Sand or grind down any rough or sharp areas.
Wash chain with degreaser to remove shipping grease.
Wash with antimicrobial agent.
Rinse well with water.
Store dry.
Directions:
Get consent and access to vagina.
Prepare the vagina by placing in a "comfortable" yet accessible position. (Lying on back, ankles near butt, and butt raised on a pillow.)
Get vagina warmed up. Wrap the chain in a towel.
Apply liberal amounts of lube to both. Be patient.
Insert chain into vagina one link at a time. (Be careful not to pinch more than her masochistic heart desires.)
Work toward orgasm(the person with chain in them), when there remove chain rapidly from vagina.