iOptron 1kg (2.2lbs) Counterweight for SmartEQ and SmartEQ Pro Mounts, White iOptron 1kg (2.2lbs) Counterweight - iOptron 1 Year Limited Warranty Compatibility: SmartEQ and SmartEQ Pro Mounts Diameter: Outer: 3" / 76.2mmInner: 0.63" / 16mm Height: 1" / 25.4mm Weight: 1kg / 2.2lbs