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Topcon 90º L-Bar Monitoring Prism (L-Bar Mini Prism)

Image of Topcon 90º L-Bar Monitoring Prism (L-Bar Mini Prism)

Description

The Topcon 90º L-Bar Monitoring Prism (L-Bar Mini Prism) is a monitoring prism made by Topcon and also sold under the Sokkia brand (part number 724814).

Its absolute prism constant is -25.0 mm, which is +9.4 mm on the Leica scale.

Specifications

Model:L-Bar Mini Prism
Manufacturer:Topcon
MPN:724814
Status:Current
Absolute constant:-25.00 mm
Leica constant:+9.40 mm
Constant source:Manufacturer documentation
Dimensions (W × H × D):90.5×90×28 mm
Prism diameter:25 mm
Weight:210 g
Maximum range:1,200 m (Up to 800-1200 m; minimum 1.5 m)
Mount:M8 adapter thread
Coating:Silver
Last verified:21/10/2026

Sources

Topcon 90º L-Bar Monitoring Prism (L-Bar Mini Prism) FAQ

Below is a list of frequently asked questions about Topcon 90º L-Bar Monitoring Prism (L-Bar Mini Prism).

What is the prism constant for the Topcon 90º L-Bar Monitoring Prism (L-Bar Mini Prism)?

The absolute prism constant for the Topcon 90º L-Bar Monitoring Prism (L-Bar Mini Prism) is -25.0mm. The Leica constant is 9.4mm.

Can I use the Topcon 90º L-Bar Monitoring Prism (L-Bar Mini Prism) with a Leica instrument?

Yes, just set the prism constant to 9.4mm.