Black Strain Reliefs, Female Thread for Pipe, Pendant Lighting, 40pk - Strain Relief Cord Grips for Wiring - 1 pack of 40 40pk Black Strain Relief with 1/8ips Female Thread Molded for screw, but does not take a screw. Used for SVT type wire. Holds cord securely in place. Safety Feature. Takes the pull off of your electrical connections.