Monitoring Prisms


1. Adjustable a direction of prism in X & Y axis easily with
 high accuracy
2. Nodal prism
 Can be set at a -41mm, which offers optimal angle
 measurements, even when tilting in either
 the horizontal or the vertical axis
3. Anchor bolt is in the set

Model Prism size Prism constant Screw size
TT-41 2.5inch (63.5mm) -41mm M8


Set contents: Base plate, Anchor


[Nodal Prism]

Surveying prisms and holders that are not in the nodal position can cause angular errors when using the prism apex as a target if it is not perfectly pointed towerd the measuring instrument.

To reduce pointing errors, Nodal prisms are designed with a nodal point alignment at -41mm offset for 2.5inch prism.

To compensate for pointing errors, nodal point alignment minimizes the error associated with misalignments.


Rain Cover for 2.5inch Prism

Full availability of the prism even in

rainy conditions. RC-25 protects the

prism front against rain drops and dust.



Code No. Product Name Model
222256 2.5inch Monitoring Base Kit TT-41
222257 Rain Cover for 2.5inch Prism RC-25