POA 70: Benefits, Use Cases, and Accuracy Explained

The POA 70, or Hilti's "Layout Point Laser," allows layout crews to achieve high accuracy while dramatically simplifying their workflow - especially in complex and imperfect jobsite conditions. With the POA 70, you can transfer layout points directly to the ground or ceiling using a visible laser point.

Note: The POA 70 is a bracket + PM 2-PG combination that allows a plumb laser to sit on a prism rod with a prism connected directly above it.

By combining a plumb laser with prism alignment, the POA 70 simplifies traditional layout workflows and significantly improves productivity - especially in real jobsite conditions.

No complex setup required: The POA 70 layout point laser is a standard Hilti 2-point plumb laser which is ready to fasten to the top of your prism rod. Once fastened, screw on your prism and you are ready to work. No software or hardware changes need to be adjusted; it's a "plug and play" solution.

Key Benefits

1. High Accuracy with Prism-to-Laser Alignment

The POA 70 uses a plumb mechanism to align the prism center to the green laser point on the ground or ceiling
Designed to meet layout accuracy requirements (+/- 3mm (~1/8") for key applications)

Accuracy is maintained even without perfect pole positioning - reduced risk of human or equipment error.

2. No Prism Pole Leveling Required; Faster Layout

Eliminates the need for bubble leveling or continuous pole adjustment (easy to adopt solution)
Simplifies navigation directly to the point
Height of rod and rod tilt have no negative impact on accuracy
- Why: The telescope measures to the center of your prism, which is already directly centered above the pendulum of the self-leveling Hilti laser. Rod height and rod tilt do not affect the pendulum's accuracy. Simply make sure your tilt does not exceed the plumb laser's visible range.

Layout tasks can be completed 2–3× faster - no need to constantly check the bubble level or recalibrate the pole.

3. Improved Ergonomics and Line-of-Sight

Allows operators to work more consistently while standing
Reduces bending, kneeling, and repositioning
Reduces need to constantly work your hands on the bipod leveling legs for your prism rod
Maintains line-of-sight to the total station at adjustable heights

Reduced fatigue, faster and more comfortable workflows.

Important User Information - Keep POA 70 in "Unlocked" Position

The pendulum for the laser needs to be in a free unlocked position for it to give you the true plumb point beneath your prism. If the POA 70 is "locked", it will not be vertically plumb.

Real Jobsite Use Cases

The POA 70 solves many challenges that traditional layout methods struggle with:

Difficult Ground Conditions

Gravel, dirt, or grass can make identifying your point with a prism pole difficult
Stabilizing the POA 70 to then identify the exact laser location ensures accuracy and speed of layout

With POA 70: locate the laser within a small area near the pole and easily clear debris (even by using your foot) to find the point.

Stake Installation and Adjustment

While hammering a stake (for point or height references), users can:
- Adjust position after each strike
- Keep the laser aligned to the stake center

With POA 70: Enables real-time corrections during installation without awkwardly holding a prism rod to the top of a narrow stake.

Marking on Edge of Raised Slabs, Forms, and Surfaces

Difficult to position a prism pole precisely on edges or raised slabs

With POA 70: Prism pole can conveniently be stabilized near the surface while the point laser identifies the needed point.

Obstructed Areas (Rebar, Tight Spaces)

Rebar congestion or obstacles can block pole placement

With POA 70: Prism pole can be stabilized near the required point, while the POA 70 gets adjusted to identify a point's location within the congested area.

Retaining Point Visibility

Traditional workflow loses the point when the pole is removed

With POA 70: Easily maintain a visible reference point during transitions from prism pole placement to point marking.

Visualizing Ground and Ceiling Points Together

Thanks to the hole centered through the bottom and top of the POA 25 , users can mark a layout point on the floor while easily referencing its vertical alignment. This allows them to quickly look up and visualize where the point will project on the ceiling, or identify potential conflicts such as ductwork, sprinkler pipes, or other obstructions.

Accuracy Considerations

The POA 70 provides a highly effective and accurate visual reference for layout marking. While the laser is positioned slightly above the prism center, the system is engineered to maintain accuracy within typical construction tolerances. Minor deviations may occur if the pole is tilted. For critical points requiring maximum precision, verification using standard prism workflows is recommended.

To give an example from a testing environment: at 1.5m height, taking into consideration the prism offset from the point laser pendulum, as well as potential tilt from the prism pole, a 3.7mm (~1/8") deviation was found with a slight prism pole tilt of ~1.7°.

If the POA 70 is tilted too far, the laser from the pendulum will no longer be visible, forcing you to readjust the prism pole. This simply further enhances your ability to maintain accuracy.

More explanation below:

System Design

The POA 70 aligns the prism center with the projected laser point using a plumb mechanism
Designed for application-level accuracy within construction tolerances

Laser Offset Reality

The telescope laser from the total station targets the prism, which is slightly above the laser's pendulum reference point. This introduces:

A small potential offset when the pole is tilted
Minor deviation depending on:
- Height of the pole
- Degree of tilt

Therefore, small deviations exist, but remain within most acceptable jobsite tolerances (high practical accuracy).

POA 70 vs Traditional Layout Methods

Feature	Traditional Prism Pole	POA 70
Leveling required	Yes	No
Setup complexity	Cumbersome	Simple
Speed	Slower	2–3× faster
Accuracy	High	High (within tolerance)
Performance in difficult conditions	Limited	Strong

Key Takeaway

The POA 70 is a workflow transformation tool, not just an accessory:

Eliminates the need for leveling
Enables faster layout execution
Improves usability in real-world conditions
Maintains accuracy within construction tolerances

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