The Lightseeker - XL rifle scopes have been redesigned and improved with larger erector lenses than conventional rifle scope designs, allowing them to give a brighter image than the competition. PENTAX's internal lenses are up to 40% larger than the competition. PentaBright means light - lots of light. Plus lightweight, one piece, aircraft aluminum construction and quick focus European style eyepieces make them tough and fast. Made in the USA. HEAVY DUTY SPRINGS - Every PENTAX scope uses either a 14-pound coil spring or two 7-pound dual bias springs secured in the tube to prevent movement under recoil. These springs exert even counter-pressure for windage and elevation adjustments. LEAKPROOF "O" RINGS - All PENTAX riflescopes are filled with nitrogen gas and are double sealed with heavy-duty neoprene "O" rings providing a lifetime seal that makes your scope waterproof and fogproof. PRECISION MACHINED CLICK ASSEMBLY - Positive and repeatable, our precision, finger adjustable windage and elevation click adjustments are easy to set and stay put after you set them. EXCEPTIONALLY THICK TUBE WALLS - Single-piece tubes, made from aircraft aluminum, have thicker walls than most scopes. EXTREMELY TOUGH RETICLES - Built and tested to withstand the heaviest recoil, PENTAX reticles are three times stronger than the industry standard. SUPER-HARD SCRATCH RESISTANT FINISHES - Outer tube surfaces are hard-anodized to prevent wear and scratches. PENTAX scopes still look good after years of hard use.