With this all-in-one tool, you'll no longer need to use a ruler or micrometer to measure spring height. Simply set the spring height with the highly refined height micrometer tube (0.01'' increments), put it in the vise and start testing. Maximum spring diameter is 1.700''. The round dial gauge measures 0-600 lbs. in 10 lb increments. The digital tester features a backlit digital display and provides accuracy from 0-700 lbs. in 2 lb. increments.