The 1.5″ (38.1mm) SMR Deluxe Kit Drop-Resistant Structure Spherically Mounted Sphere for Laser Tracker contains:

Hollow Reflector *1
• K9 Optical Glass
• Drop-resistant Structure
• Stable Multi-Layers Coating
• 5arcsec Beam Deviation
• 80m Working Range

Hardened Steel Sphere * 1
• 1.5inch Diameter
• SUS-440C Steel

Removable Ring *2
One with wristband

Better Than 0.0003″
Rotating Offset