Click for larger image and other views Image is representative of the product family. Select individual products in the table below for more specific images and product specifications

How can we improve our images or Product Specifications?

Starrett 120M Series Dial Caliper, Stainless Steel, Metric, For Inside/Outside Measurements

Be the first to review this item

Product Specifications
Manufacturer Series Number
120M Series
Specific Uses For Product
Inside , Outside
Tip Description
Material Type
Stainless Steel
Brand Name
System of Measurement

This item is no longer available

These items ship for FREE with 2-Day Shipping on orders over $50. (Details)

Want it delivered on Tue, Apr 21? Order in-stock items in the next 1 day 23 hrs 52 mins and choose One-Day Shipping at checkout.

  • Share
Currently showing 1-9 of 9
Range Resolution Measurement accuracy Part number ASIN

The Amazon Standard Item Number (ASIN) uniquely identifies
the item in the (and Amazon) catalog.


If an item is currently out of stock, but has an estimated lead time, you can place an order now and we will ship it as soon as it is available.
You can also order more than we currently have in stock.
Read more about back orders in our help section.

All All All All      
Currently showing 1-9 of 9
0-150mm 0.02mm +/-0.03mm 120AM-150 B000FMX3PM yes $207.00 Buy Options
0-150mm 0.02mm +/-0.03mm 120MX-150 B003XU78NG yes $303.00 Buy Options
0-150mm 0.02mm N/A 120AM-150 W/SLC B000VDXJ18 yes $207.01 Buy Options
0-225mm 0.02mm +/-0.03mm 120M-225 B000VDXJ1S Usually ships in 24 hours $310.00 Buy Options
0-225mm 0.02mm +/-0.03mm 120MZ-225 B001B0TG76 yes $352.00 Buy Options
0-300mm 0.02mm +/-0.03mm 120M-300 B001B0SKW8 yes $370.00 Buy Options
0-300mm 0.02mm +/-0.03mm 120M-300 W/SLC B003XU78MW yes $410.00 Buy Options
0-300mm 0.02mm +/-0.03mm 120MZ-300 B000VDTHL4 yes $413.00 Buy Options
0-300mm 0.02mm +/-0.03mm 120MZ-300 W/SLC B003XU78NQ yes $402.48 Buy Options

Key Features

  • Precise dial graduations of 0.02 mm, with one revolution equivalent to 2 mm
  • Thumb-operated fine adjustment roll for one-hand use
  • Lock screw holds the sliding jaw in position, to ensure a consistent measurement
  • Rack teeth point down to keep foreign matter from clogging the gear, to help prevent measurement error
  • Knife-edge contacts for inside and outside measurements

Product Description

The Starrett 120AM-150 dial caliper measures 0 to 150 mm with 0.02 mm accuracy. This handy measuring tool allows for reliable and accurate readings with the sharp, black graduations on the no-glare, satin-finished bar, crisp lines on the yellow dial face, and knife edge contacts for inside and outside measurements.

One full revolution of the dial is equivalent to 2 mm. The jaw depths on this caliper are approximately 1-1/2” or 38 mm for the outside measuring jaws and 5/8" or 16 mm on the inside measuring jaws. The jaw depths on this caliper are approximately 1-1/2” or 38 mm for the outside measuring jaws and 5/8" or 16 mm on the inside measuring jaws. The knife-edge contacts can be used to scribe parallel lines on the workpiece. This caliper can be used with one hand through operating the fine adjustment roll with the thumb. The lock screw locks the dial bezel and holds the sliding jaw in position. The depth rod is integrated into the rack of the caliper, unlike many calipers which offer a detachable depth rod, or none at all. The hardened stainless steel components, including the bar, measuring surfaces, rack, gears, and depth rod, offer corrosion resistance, increased accuracy, and long life. Positive split gear anti-backlash control offers increased accuracy over standard gear configurations. Backlash is the amount of clearance between mated gear teeth in the caliper controls, which prevents the gear teeth from jamming. It is undesirable to have much backlash due to the lack of precision offered by the increased amount of play between gears. Certain gear designs can minimize or eliminate backlash; split gear systems actually split the gear into two gears, each half as thick as the original gear. One of these gears is then fixed to the shaft while the other gear is allowed to turn. The free-turning gear is connected to coil springs that rotate it until all the backlash in the control system has been eliminated. The rack teeth point down to keep foreign matter from clogging the gear operations. This prevents measurement errors where metal chips could interfere with proper caliper operation.

Calipers measure the distance between two opposing sides of an object. They make inside, outside, depth, or step measurements, according to their type. Calipers are commonly used in architecture, metalworking, mechanical engineering, machining, manufacturing, carpentry, and medicine. The simplest calipers have two legs to mark the two points and require a ruler to take the measurement. More complex calipers use two sets of jaws instead of legs and have up to two graduated scales. Vernier, dial, and digital calipers give direct and accurate readings and are functionally identical, having a calibrated scale with a fixed jaw, and another jaw with a movable pointer that slides along the scale. The vernier caliper has a scale sliding parallel to the main scale for an additional, fractional reading to improve measurement precision. The dial caliper has a circular dial with a pointer on a toothed gear rack replacing the second vernier scale. As with the vernier, this second measurement is added to the reading from the main scale to obtain the result. The dial caliper is used also for measuring size differential between two objects. The digital caliper takes the same sort of differential measurements as the dial caliper by zeroing the display at any point along the slide, with an LCD (replacing the dial) that displays a single, easily read value in both English and metric units. Some digital calipers can hold data readings between measurements and send them to data collection devices.

The L. S. Starrett Company was founded in 1880, originally manufacturing bench vises, squares, and other tools. They acquired other companies throughout the years, expanding their services into making precision measurement instruments and tools, such as calipers, micrometers, saw blades, and gauges. Starrett is headquartered in Athol, Massachusetts and has manufacturing facilities in Brazil, the United Kingdom, China, and other locations.

How can we improve our Product Description?

Customer Reviews

There are no customer reviews yet.

Be the first to review this item

Go to the HomePage

Order by Phone
M-F 8am-10pm ET, Sat-Sun 8am-5pm ET 800-220-4242

My Account| Returns| Help

Website Feedback| Contact Us| Sell on AmazonSupply| Become an Affiliate

Privacy Notice| Conditions of Use

Follow Us 

© 2015, Inc. and its affiliates.