After grocery shopping, I was putting items into the back seat on the floor of the truck. I lifted the seats to allow for more room. I went to push an item to the far side of the truck to allow for more room. During this action, I put my left hand down with my knuckles facing the floor to provide leverage. without realizing where I was putting my hand, I placed the middle segment of my ring finger directly on the edge of the mechanical-jack and put my weight onto it. The jack is not covered and is black (the same color as the carpet). The edge of the jack has sharp burrs. As a result, I was cut across the entire middle segment of my ring finger and slightly on the knuckle of my middle finger.