Butterfly Coal Miner Steel Knife. This stainless steel blade comes in a tanto style with the entire body covered in a stonewash finish. The handle is double walled with a steel frame. Each piece is riveted together even the pivot pins are rivets. With a sturdy construction such as this, how can you beat this deal? The tanto style blade has become popular for its extra cutting edge. This knife comes double pinned. The reason for this is to hold the blade away from the handle when closed to prevent dulling; and, in some cases, a second pin to keep the handles from excessively banging together while the butterfly knife is being manipulated. A safety latch is provided for locking your blade opened or closed. Overall Length: 8.75 Inches.