Description
The Topcon Economy Tilting Prism Assembly with 5½ x 7 in. Target (silver coated 62 mm) – 0 mm position is a survey prism made by Topcon and also sold under the Sokkia brand (part number 60857-SURSK (orange), 724808 (yellow); mounts only: 724804, 724805).
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: | Economy Tilting Prism Assembly 5.5x7 |
| Manufacturer: | Topcon |
| MPN: | 60857-SURSK (orange), 724808 (yellow); mounts only: 724804, 724805 |
| Status: | Current |
| 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 |
| Mount: | Rear-locking economy tilting mount, 5½ x 7 in. target |
| Coating: | Silver |
| Housing: | Sealed canister |
| Last verified: | 21/10/2026 |
Sources
Topcon Economy Tilting Prism Assembly with 5½ x 7 in. Target (silver coated 62 mm) - 0 mm position FAQ
Below is a list of frequently asked questions about Topcon Economy Tilting Prism Assembly with 5½ x 7 in. Target (silver coated 62 mm) - 0 mm position.
What is the prism constant for the Topcon Economy Tilting Prism Assembly with 5½ x 7 in. Target (silver coated 62 mm) - 0 mm position?
The Topcon Economy Tilting Prism Assembly with 5½ x 7 in. Target (silver coated 62 mm) - 0 mm position 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 Topcon Economy Tilting Prism Assembly with 5½ x 7 in. Target (silver coated 62 mm) - 0 mm position with a Leica instrument?
Yes, just set the prism constant to 34.4mm (or 4.4mm in the second position).
