Commercial Specification Grade Straight Blade Plugs and Connectors are rugged performers. ; They are moisture, chemical and abuse-resistant. And they're ideal for indoor and outdoor use.; All of these features and benefits are common to 15 A and 20 A Commercial Specification Grade Plugs and Connectors; TPE rubber-backed plugs and connectors stand up to rough use, protect against dirt and moisture. Deep-slotted, backed-out terminal screws draw backwire clamps securely over stripped leads for maximum conductivity.