Benefits: The Kowa 99mm TSN-99 Prominar Spotting Scope offers an amazing viewing experience in a rugged and durable housing that is fully waterproof and nitrogen-filled Fully Waterproof and Nitrogen Sealed: The scope body is fully sealed to protect from the elements. The rugged structure can tolerate the severest conditions and provides confidence and a sense of security Features: Quick focus allows for fast action to bring your subject into detail in just a few smooth revolutions, whilst Fine focus gives pin-point, finger-tip control offering the ultimate in focussing accuracy with minute adjustments possible even when wearing gloves