Trijicon 20-60x82 HD Spotting Scope Fully Broadband Multi-Coated Fluoride Lenses facilitates superior light transmission, color fidelity, clarity and avoids chromatic aberration Waterproof and Dry Nitrogen Filled - Stands up to all weather conditions and eliminates inside lenses from fogging Incorporating a magnesium body allows maximum strength and reduce the overall weight for a durable, highly portable and lightweight spotting scope Dual-focus knob for precise focus clarity Angled eyepiece with body indexing feature allows for 225 degree vertical rotation