HARDELL Rechargeable-150MM Digital Caliper, 6-Inch Metal, USB-C, Backlit

The 6-inch metal body gives this digital caliper a compact format for measuring parts around a workbench, home, or project space. Its backlit screen makes readings easier to see in different lighting. Switch between inches, millimeters, and fractions, then choose from four measurement modes. It’s a practical alternative to a basic ruler when a project calls for more specific measurements.

Spec sheet

• Type: Digital caliper
• Model: Rechargeable-150MM
• Material: Metal
• Range: 6 inches
• Accuracy: ±0.001"/0.02mm
• Resolution: 0.0005"
• Measurement units: Inches, millimeters, and fractions
• Measurement modes: Internal, external, depth, and step
• Display: Backlit LCD
• Charging: Rechargeable, USB-C

The four modes cover common measuring tasks with one tool: check an object’s outside dimensions, measure an opening or inside diameter, gauge depth, or compare a step between surfaces. Changing units and selecting fraction readings helps the display match the way you work, whether you’re checking a component for a repair or sizing a piece for a build.

How to use it

Slide the caliper around or into the feature you want to measure, then select the mode that matches the task: external, internal, depth, or step. The digital display provides the reading in your selected unit, so you can move between inch, millimeter, and fraction measurements without relying on a separate conversion. For example, when checking a 3D-printed part, you can measure an outside edge, inspect an opening, or check a surface step with the same tool.

The backlight is activated with the LIGHT button, making the screen easier to read in a dim garage or other low-light work area. It shuts off after five seconds, while the caliper powers down after five minutes of inactivity. To charge it, use a 5V adapter and a USB-C cable. Avoid adapters above 7V and dual USB-C (Type-C to Type-C) cables, which may not charge the caliper correctly.

Tips for day-to-day use

Choose the measurement mode before taking a reading, and check that the caliper is positioned against the surfaces you intend to measure. Switching between inches, millimeters, and fractions is useful when a project’s reference or plans use a different format than your usual measurements. The thumb roller and sliding action support controlled positioning for repeated checks on small parts, woodworking joints, household repair pieces, or model components.

For a quick check at a workbench, you might measure a part’s outer width, then use the internal jaws to size an opening. If you’re working in a dim area, press LIGHT to make the reading easier to see. Rechargeable USB-C power provides a charging option in place of routine battery replacement, use the specified charging setup when topping it up.

When it makes sense

This caliper suits projects where a ruler’s markings are not the most convenient way to check dimensions, but a specialized tool for only one kind of measurement would be less flexible. Its internal, external, depth, and step modes make it useful across DIY repairs, 3D printing, woodworking, and other tasks involving varied part shapes. The choice of inch, millimeter, or fraction readings also helps when you need to work from different measurement references.

Buyers commonly highlight the readable display, backlight, rechargeable USB-C connection, and solid feel. Some also mention using it for 3D-printing measurements and appreciate the fraction mode. For home projects or a workshop routine that calls for one compact tool to handle several kinds of measurements, the 6-inch range, metal construction, and four selectable modes bring useful versatility to the bench.