Adams super-strong suction cups are produced from high-quality material that won't yellow, deteriorate, or lose adhesion over time. Light diffusing rings prevent focused light from damaging surfaces. Holding securely in all types of weather, Medium Suction Cups hold up to 3 lbs. Deep hook design is ideal for window-mounted holiday ornaments, stained glass and decorationsOnce applied, not affected by heat or coldStrong, rustproof metal hooksSuction Cup design diffuses light to prevent surface damage3 lbs. capacityWill not yellow or deteriorate