Seco Heavy-Duty Instrument Column Clamp The Seco 4852-18 Heavy-Duty Instrument Column Clamp is designed for securely mounting 5/8" x 11 surveying instruments to structural columns in industrial and construction environments. It provides a rigid, stable platform for heavy instruments where ground-based setups are impractical. The adjustable column allows both vertical movement and rotation , offering up to 12 inches (30.48 cm) of height adjustment for precise instrument positioning. It includes a 20-inch 3/4" NPT pipe with heavy-duty sliding clamp , providing additional mounting flexibility and extension capability for field setups. Constructed from structural aluminum with stainless steel hardware, this system is engineered for long-term durability and stability in demanding applications. Key Features • Supports all 5/8" x 11 threaded survey instruments • Designed for mounting to structural columns in industrial environments • Adjustable column with 12" (30.48 cm) vertical range and rotation capability • Includes 20" 3/4" NPT pipe with heavy-duty sliding clamp • Centerline offset: 15" (38.1 cm) from stud to column • Structural aluminum construction with stainless steel hardware • Built for heavy-duty surveying and industrial applications