Prexiso P40A
PREXISO Pocket Laser Measurement Tool
Model: P40A
Brand: Prexiso
1. Introduction
This user manual provides detailed instructions for the operation and maintenance of your PREXISO Pocket Laser Measurement Tool. This compact and accurate device is designed for various measurement tasks in home, construction, and industrial environments. Please read this manual thoroughly before using the device to ensure safe and proper operation.
1.1 Safety Information
WARNING: Laser Radiation
This device emits Class 2 laser radiation. Do not stare into the beam. Maximum laser output is less than 1mW. Complies with 21 CFR 1040.10 and 1040.11 except for conformance with IEC 60825-1 Ed. 3, as described in Laser Notice No. 56, dated May 8, 2019.
Always ensure the laser beam is not directed at people or animals. Avoid direct eye exposure.
2. Package Contents
Verify that all items listed below are included in your package:
- 1 x PREXISO Penlaser 131Ft Mini Laser Distance Measure
- 2 x 1.5V AAA Alkaline Batteries
- 1 x User Manual (this document)
- 1 x Package Box
3. Product Overview
The PREXISO Pocket Laser Measurement Tool features a compact, pen-style design for easy portability and handling. It incorporates an advanced ASIC chip for high accuracy and efficient power consumption.
Figure 3.1: PREXISO Pocket Laser Measurement Tool and included batteries.
This image shows the compact design of the laser measurement tool, held comfortably in a user's hand, alongside the two AAA batteries required for operation.
Figure 3.2: Key Components of the Device.
This diagram highlights the main functional parts of the laser measurement tool, including the laser beam outlet, backlit display screen, power/measure button, function button for area/volume/addition/subtraction, and the integrated pen clip.
Figure 3.3: Display Icons and Indicators.
This image provides a detailed view of the device's backlit display, illustrating the various icons and indicators for measurement reference, addition/subtraction, battery status, area/volume modes, and selected units.
4. Setup
4.1 Battery Installation
The device requires two 1.5V AAA alkaline batteries. Ensure correct polarity when inserting the batteries.
- Locate the battery compartment cover on the back of the device.
- Slide the cover open.
- Insert two AAA batteries according to the polarity markings (+/-) inside the compartment.
- Close the battery compartment cover securely.
Figure 4.1: Battery Installation.
This image demonstrates the process of opening the battery compartment and inserting the AAA batteries into the PREXISO laser measurement tool.
4.2 Power On/Off
- To power on the device, press the ON button. The backlit display will illuminate.
- The device will automatically shut down after 120 seconds of inactivity to conserve battery life.
5. Operating Modes
The PREXISO laser measurement tool offers six different measurement modes:
Figure 5.1: Multiple Measurement Modes Overview.
This visual guide illustrates the different measurement functions available on the device, including continuous, volume, area, and arithmetic operations.
5.1 Single Distance Measurement
This is the default mode for measuring a single distance.
- Ensure the device is powered on.
- Point the laser beam at the target.
- Press the ON button once. The measurement will be displayed instantly.
Figure 5.2: Distance Measurement in Use.
This image depicts the laser measurement tool actively measuring a distance within a room, demonstrating its practical application.
5.2 Continuous Measurement (Tracking)
This mode allows for continuous measurement as you move the device, displaying real-time distance updates.
- From single distance mode, press the FUNC button repeatedly until the continuous measurement icon appears on the display.
- Move the device slowly towards or away from the target. The display will update continuously.
- Press the ON button to stop continuous measurement and hold the last value.
5.3 Area Measurement
To calculate the area of a rectangular space.
- Press the FUNC button until the area measurement icon appears.
- Measure the first side (e.g., length) by pressing ON.
- Measure the second side (e.g., width) by pressing ON again.
- The calculated area will be displayed.
Figure 5.3: Area Measurement Application.
This image illustrates how the laser measurement tool can be used to define and calculate the area of a room or surface.
5.4 Volume Measurement
To calculate the volume of a space.
- Press the FUNC button until the volume measurement icon appears.
- Measure the length by pressing ON.
- Measure the width by pressing ON.
- Measure the height by pressing ON.
- The calculated volume will be displayed.
5.5 Pythagorean Measurement (Indirect Measurement)
This mode uses the Pythagorean theorem to calculate distances indirectly, such as height or length, when direct measurement is not possible.
5.5.1 Two-Point Pythagorean Method
Used to calculate the height of an object when you can measure the hypotenuse and one leg.
- Press the FUNC button until the two-point Pythagorean icon appears.
- Measure the hypotenuse (e.g., from the base of the device to the top of the object) by pressing ON.
- Measure the horizontal distance (e.g., from the device to the base of the object) by pressing ON.
- The calculated height will be displayed.
5.5.2 Three-Point Pythagorean Method
Used for more complex indirect height measurements.
- Press the FUNC button until the three-point Pythagorean icon appears.
- Follow the on-screen prompts to measure the three required distances.
- The calculated height will be displayed.
6. Unit and Reference Settings
6.1 Changing Measurement Units
The device supports Ft (feet), Ft+In (feet and inches), In (inches), and M (meters).
- Hold the FUNC button for 3 seconds to enter Unit Setting Mode.
- Press the FUNC button repeatedly to cycle through the available units.
- Press the ON button to confirm your selection and exit Unit Setting Mode.
Figure 6.1: Unit and Reference Adjustment.
This detailed diagram illustrates the steps for changing measurement units and adjusting the measurement reference point (front or rear of the device).
6.2 Changing Measurement Reference
The device can measure from its front (laser beam outlet) or its rear (base of the device). The default is usually from the rear.
- Press the FUNC button for 3 seconds to enter Measurement Reference Mode.
- Press the FUNC button again to toggle between front and rear reference points. An icon on the display will indicate the current reference.
- Press the ON button to confirm your selection and exit Measurement Reference Mode.
7. Maintenance
7.1 Cleaning
To maintain accuracy and prolong the life of your device:
- Wipe the device with a soft, damp cloth. Do not use abrasive cleaners or solvents.
- Clean the laser lens carefully with a soft, lint-free cloth, similar to cleaning camera lenses.
7.2 Storage
- Store the device in a cool, dry place, away from direct sunlight and extreme temperatures.
- Remove batteries if the device will not be used for an extended period to prevent leakage.
8. Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Device does not power on. | Low or dead batteries; Incorrect battery installation. | Replace batteries; Check battery polarity. |
| Inaccurate measurements. | Laser lens dirty; Measurement surface too reflective/absorbent; Device not stable during measurement. | Clean laser lens; Use a target plate for difficult surfaces; Ensure device is stable. |
| Display is dim or flickering. | Low battery. | Replace batteries. |
| Error message on display. | Measurement out of range; Obstruction in laser path. | Ensure target is within 131ft range; Clear laser path. |
9. Specifications
| Feature | Detail |
|---|---|
| Model Name | P40A |
| Measuring Range | Up to 131 feet (40 meters) |
| Accuracy | ±1/8 inch (±3mm) |
| Measurement Units | Ft, Ft+In, In, M |
| Laser Class | Class 2, <1mW |
| Power Supply | 2 x 1.5V AAA Alkaline Batteries |
| Automatic Shutdown | 120 seconds (laser), 180 seconds (device) |
| Material | Plastic |
| Water Resistance | IP54 (Waterproof) |
| Item Weight | 0.09 Kilograms |
| Dimensions (LxWxH) | Approx. 9.84 x 7.87 x 3.15 inches (Package) |
Figure 9.1: Measurement Accuracy.
This image highlights the precision of the laser measurement tool, indicating an accuracy of ±1/8 inch or ±3mm.
10. Warranty and Support
10.1 Warranty Information
This PREXISO product comes with a 24-month warranty from the date of purchase, covering defects in materials and workmanship under normal use. This warranty does not cover damage caused by misuse, unauthorized modification, accident, or neglect.
Please retain your proof of purchase for warranty claims.
10.2 Customer Support
For technical assistance, warranty claims, or general inquiries, please contact PREXISO customer support through the official website or your retailer. Refer to the product packaging or official PREXISO website for the most current contact information.
For more information, visit the Prexiso Store.
Ask a question about this manual
Ask about setup, troubleshooting, compatibility, parts, safety, or missing instructions. Manuals+ will review the question and use this page’s manual context to help answer it.

