This 7" Set Gives You Both Straight And Rounded Calipers To Measure With Inside, Outside, And Divider. Locking Screw Mechanism Assures Accuracy. Adjustable Screw Is About 2" Long And The Knob Is About 1/16" To Make Overall Screw Length Little Less Than 2".

* This 3 piece set includes inside, outside and divider calipers-set weighs 8.4 ounces

* Made of heavy duty grade aluminum-this set is ideal for many types of measuring

* Measure inside of an opening, outside the opening, & circumference of round items

* These tools have many applications in workshops and even science labs

* Excellent classroom and instructional tools for many types of study-accurate & reliable