I may not be able to reply, or may not be able to reply, on Saturdays through Tuesdays. Please be aware of this. You can measure the thickness of the tip of a shinai (bamboo sword). To use it, simply place the tip of the shinai of the indicated size into the recess. If it falls into the recess, it does not meet the regulations and is NG. This item allows you to easily measure your own shinai. Made of plastic, it's lightweight and compact size (H15cm x W10cm). It's reassuring to have checked it beforehand during the pre-match inspection.