BEST CHOICE FOR SURVEYING- This tribrach adapter is great for surveying large areas and making sure your levels are centered GREAT FOR LEVELING - Twist Focus Tribrach features twist focus and leveling screws with center line. PROFORM BEST ACCURACY- 8-minute circular vial. s in a tripod, stability in a tribrach is a significant factor in measurement accuracy. Focusing range of 1.5~15 METER (1.5 to 50 feet. ADJUST SMOOTHLY- Footscrews have a large diameter for fine adjustment even when wearing gloves DURABLE FOR YEARS - Anodized black aluminum is heavy duty and premium quality meant to last through wear and tear, Manufacturer: Mountlaser