Inert Training Pepper Spray Units For training purposes, Def-Tec/Federal Laboratories offers inert aerosols in all delivery systems and canister sizes. Inert Training Pepper Spray Units DT-51Regular price: $15.95Sale price: $13.95Choose: MK-3MK-4(+1.60)MK-6(+3.75)MK-9(+21.03) Copyright 2012 Police Supply Online providing Police Equipment to over 300 Police, Federal & Military Law Enforcement Agencies around the world.