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Seco -30/0 mm Premier Prism Assembly (6 x 9 inch target)

Image of Seco -30/0 mm Premier Prism Assembly (6 x 9 inch target)

Description

The Seco -30/0 mm Premier Prism Assembly (6 x 9 inch target) is a survey prism made by Seco (part number 6402-06-FLB / 6402-06-FOB / 6402-06-YLB).

It can be set up in two positions, giving an absolute prism constant of 0.0 mm or -30.0 mm (+34.4 mm or +4.4 mm on the Leica scale). Always check which position is in use before measuring.

Specifications

Model:6402-06
Manufacturer:Seco
MPN:6402-06-FLB / 6402-06-FOB / 6402-06-YLB
Status:Current
Height Offset:100.0 mm
Absolute constant:+0.00 mm or -30.00 mm
Leica constant:+34.40 mm or +4.40 mm
Two mounting positions. Check which one is in use before measuring.
Constant source:Manufacturer documentation
Prism diameter:62 mm
Weight:800 g
Mount:5/8" Thread
Coating:copper
Housing:heavy-duty canister; anodised aluminium tilting holder
Equivalents:Marketed for Nikon, Topcon and Sokkia total stations
Last verified:21/10/2026

Sources

Seco -30/0 mm Premier Prism Assembly (6 x 9 inch target) FAQ

Below is a list of frequently asked questions about Seco -30/0 mm Premier Prism Assembly (6 x 9 inch target).

What is the prism constant for the Seco -30/0 mm Premier Prism Assembly (6 x 9 inch target)?

The Seco -30/0 mm Premier Prism Assembly (6 x 9 inch target) has two mounting positions. The absolute prism constant is 0.0mm or -30.0mm. The Leica constant is 34.4mm or 4.4mm.

Can I use the Seco -30/0 mm Premier Prism Assembly (6 x 9 inch target) with a Leica instrument?

Yes, just set the prism constant to 34.4mm (or 4.4mm in the second position).

What is the height offset of the Seco -30/0 mm Premier Prism Assembly (6 x 9 inch target)?

The height offset is 100.0mm.