Aura Cord-clamp&trade; Orange Rubber Extension Cord Clamps Organizer - Pack of (2) These clever little rubber cord clamps will keep your power and extension cords from pulling apart Besides that, the knot can get hung up on stuff when you pull on the cord. The Cord-Clamp takes cords up to approx 7/16" OD and has a 3" long space in the middle to hold the plugs. ndoor and outdoor use. Made by those extra-cautious Canadians. Made in Canada.