INCREMENT BORER: 25cm of length, 5mm of core diameter, 2-threading. Increment Borer is a specialized tool to determine the age and the growth increment of a tree by exacting a section of wood tissue from a living tree with relatively minor injury to the plant. By examining the core sample, the user can reveal several indices of a tree, such as growth rate, age, compactness, even including pollution status of the environment where the tree lives and nutrient transport in the tree. Features: Made of high quality steel imported from Japan. Manufactured by advanced heat treatment and precision machining. Good quality, easy to take samples, complete, flat and smooth, etc. The handle is made of aluminum alloy with sand blasting and anodic oxidation treatment.