Earthing Photonic Blanket & Sheet Set of 1 each Includes one grounding cord for the outlet. After purchasing and using for a while, it was stored for several years, so there is a feeling of use. No returns. The earthing blanket can be wrapped around a pillow for earthing of the head, so it is sold as a set with the earthing sheet. *Please prepare a circuit tester screwdriver as it is not included. How to check the ground from the seller, Shirahime Labo: For safe use, be sure to check which side of the outlet is grounded with a circuit tester screwdriver before use! Use is solely at the customer's own risk! For outlets: When inserted into the outlet holes, the red lamp on the circuit tester screwdriver will light up on the side where electricity is flowing. The red lamp will not light up in the ground hole. Insert the grounding cord into the ground hole where the lamp does not light up. "Caution" Here's something very important: Always connect to the ground side of the outlet. If both sides light up, the wiring may not be correct, so do not insert the grounding cord in that case. It's dangerous. Use the alligator clip on the other end of the grounding cord to clip onto the black part of the blanket or sheet. #Earthing #EarthingMat