Capsuled coins are held in place by two flexible silicone membranes which make the challenge coin appear to be "levitating" in the frame. These membranes will. Indeep Thin Blue Line Police Officer Challenge Coin United States Spartan Warrior Law Enforcement Coins. out of 5 stars 9% off. This beautiful designed challenge coin honors the Delaware State Police Civilian Employees who have dedicated their careers to support law enforcement.