Two specially hardened steel wheels are positioned at the optimum angle for quickly restoring a sharp edge. All you need to do is pull the blade through the wheels a few times and like magic, a sharp edge is restored! This sharpener is designed specifically for Rada knives and works best with thin bladed knives. 3 1/2 inches long by 1 1/2 inches wide by 2 inches tall. Package of 6 sharpeners for cost savings.