Dual Slope Grade Laser Built for Complex Site Grading Operations
The Spectra Precision GL422N-NR is a professional-grade dual slope laser designed for contractors who need to control two independent slopes simultaneously. Whether you're grading crowned roadways, drainage swales, parking lots, or multi-directional pads, the GL422N-NR brings precision and repeatability to your most demanding site work. Paired with the included HL760 laser receiver, this system delivers the accuracy and durability that grading crews depend on day in and day out.
Overview and Jobsite Applications
Unlike single-slope lasers that limit you to one grade direction at a time, the GL422N-NR lets you set and hold two independent slopes in the X and Y axes at the same time. This means your motor grader operator, scraper, or blade operator gets real-time grade control across both planes without resetting the instrument between passes. The result is fewer setups, faster cycle times, and tighter tolerances on finished grades. The GL422N-NR is built for outdoor use in demanding conditions, with a rugged housing, self-leveling capability, and a working range of up to 2,200 feet in diameter — enough to cover large commercial sites, road projects, and subdivision developments from a single setup.
Key Specifications
- Slope Range: 0–10% in both X and Y axes simultaneously
- Self-Leveling Range: ±5° automatic
- Working Radius: Up to 1,100 ft (335 m) — 2,200 ft diameter
- Accuracy: ±1.5 arc seconds (±1/16" at 100 ft)
- Rotation Speed: 100, 300, or 600 RPM selectable
- Laser Class: Class IIIa (Class 3R), 635 nm visible red
- Battery Life: Up to 100 hours on 4 D-cell alkaline batteries
- Operating Temperature: -20°C to +50°C (-4°F to 122°F)
- Receiver Included: HL760 laser receiver
Key Features
- True Dual Slope Control: Set and hold independent X and Y slopes simultaneously for complex grading without repeated instrument repositioning
- Remote Slope Control: Compatible with RC402N remote control for adjusting grade settings from the cab of the machine
- Automatic Self-Leveling: Levels within ±5° and alerts operator if level is lost during operation
- Out-of-Level Alarm: Audible and visual alarm system stops rotation if the instrument is disturbed
- Long Battery Life: Up to 100 hours on standard D-cell batteries keeps the instrument running through long shifts
- Rugged Housing: IP66-rated dust and water protection handles harsh jobsite environments
- HL760 Receiver Included: Long-range receiver with large catch zone and audible/visual grade indication
- Selectable Rotation Speed: Three speed settings optimize visibility across different lighting and working distance conditions
Job Applications
Crowned Road and Parking Lot Grading: Set opposing cross-slopes simultaneously to achieve precise crowned profiles on roadways and parking areas in a single instrument setup.
Drainage Swale and Detention Basin Work: Control longitudinal and cross-fall grades at the same time to hit tight drainage design grades on swales, channels, and retention basins.
Commercial Site Pad Preparation: Grade large building pads with complex multi-directional slopes, reducing the number of setups and keeping machines on grade through the full pad area.
Subdivision and Land Development: Cover large development sites from a single instrument position, controlling finished grade across roads, lots, and drainage infrastructure simultaneously.
Compatible Accessories
- RC402N Dual Slope Remote Control — Adjust X and Y slopes from the machine cab without leaving the seat
- HL760 Laser Receiver — Long-range receiver included; replacement and additional units available
- LD8 Machine Mounted Display — In-cab display for machine control applications
- Spectra Tripod and Grade Rod Accessories — Heavy-duty tripods and grade rods optimized for laser setups
Related Guides
- How to Set Up a Dual Slope Laser for Crowned Road Grading
- GL422N-NR vs GL422N: What's the Difference?
- Choosing the Right Grade Laser for Your Site Work
- Using the RC402N Remote with the GL422N-NR
Frequently Asked Questions
- What does the "NR" designation mean on the GL422N-NR?
- The "NR" indicates the unit does not include a remote control. The GL422N-NR comes with the HL760 receiver but without the RC402N dual slope remote. The remote can be purchased separately and is fully compatible with this model.
- Can the GL422N-NR be used for machine control applications?
- Yes. The GL422N-NR is compatible with Spectra Precision machine control systems. When paired with compatible sensors and an in-cab display such as the LD8, it can provide automated blade control on motor graders and dozers.
- What is the maximum slope the GL422N-NR can hold?
- The GL422N-NR can hold slopes from 0% to 10% in both the X and Y axes simultaneously. This covers the full range of typical civil grading work including steep drainage and access road grades.
- Does this laser work in bright sunlight?
- Yes. The included HL760 receiver is designed to detect the laser beam in full sunlight at working distances up to 1,100 feet, where the naked eye cannot see the beam. The receiver's audio and visual indicators guide the operator on grade in any lighting condition.
