Much like that hot girlÌ´Ì_you never thought you would have the pleasure of seeing again, the Microtech LUDT is back and better than ever. There are a host of differences and the most recognizable is the blade which features a smooth spine and notched thumb ramp. Lots of milling in the 6061 T6 OD green aluminum handle make for a very sweet looking knife. The UDT (Underwater Demolition Team) knife was introduced by Anthony Marfione over 20 years ago. This is the larger version or LUDT in his line of UDT automatic knives. The 3.4 inch blade is perfect for EDC use. All hardware is stainless steel including pocket clip.