Fishing Line Counter Digital Clip-on Yardage Deepth Gauge 999FT 10 Groups Data Trolling Jigging 180 Degree 2-Way Adjustable LED Screen Unit Feet/Meter switch. Maximum counting length is 999.99m(or ft) each group, resolution 0.1m(ft). Memory Mode Available. Can store up to 10 groups of individual counting data. So if expecting counting length is longer than 999.99m(or ft), you can split up the whole length into serval sections and store in different groups, then sum all groups' datas up. Means counting maximum length 9999.9m(ft) technically. 180 degree Rotating. Work for rods with trigger handle(casting rod) and spinning handle(spinning cods), even flexible functionality on boat for trolling, jigging, deep dropping. Will work as a yarn counter too. Heavy duty ABS side plate; strong clip-on clamp with soft rubber inner; smooth line wheel. (Tips: double wrapped around the wheel to reduce slippage and increase accuracy.) Electronic model LED screen. Supported by one 2032 Battery (do not supply). Please mail to ask for an ENGLISH INSTRUCTION if it is needed.