Hasp and Hasp Lock, 3 1 2 in, Silver no checkout Added carbon layer helps filter Added carbon layer helps filter out nuisance levels of ozone and organic vapors (less than OSHA PEL) For most welding applications HandyStrap® with buckle allows mask to comfortably hang around neck when not in use Ventex® valve lets the hot air out faster so workers stay cooler The solid black color stays cleaner looking longer preventing pre mature disposal heavyweight For use with oil and petroleum based fluids Accepts shackle diameter up to 11 32in (9mm) Zinc plated hardened steel for added strength and weatherability Hardened steel staple resist cutting and sawing Hardened steel locking eye for strong cut resistance Tamper proof hinge help resist prying