Perfect Measure Tool: Quick and accurate way to measure your catch. Features a diagrams gender for easy identification. High Quality: made of high-density thick plastic materials, with clear digital identification and measurement methods, make your use of the process more convenient and simple. ABS will not expand or contract in heat or cold. Convenient: There is a small hole on the top right, which can connect your lanyard. Easy to carry. Wide Range of Uses: Accurate measurement of the legal size of many species of crabs, clams and shrimps. CUSTOMER SATISFACTION & PRODUCT QUALITY ARE OUR FIRST PRIORITY: If you have any question about our products and service, please feel free to contact us, we will reply within 24 hours.