Durable Construction: Made from aluminum alloy material, weighing only 5.2 ounces for lightweight portability without sacrificing strength and durability Compatible Design: Tripod mount ring specifically designed for 70-200mm F4 lens with 2.7-inch inner diameter and 1/4-inch screw hole interface for secure attachment Quick Installation: Easy-to-mount design with 0.8-inch ring width allows for fast setup and smooth rotation for switching between landscape and portrait orientations Balanced Stability: Provides hands-free support and relieves hand fatigue during extended sessions while maintaining optimal balance on tripod or monopod Lens Protection: Features high-grade corduroy interior lining that prevents scratches and wear on your lens Drum during mounting, use, and storage