· Include Step Up Filter Adapter Ring Kit(37-49, 49-52, 52-55, 55-58, 58-62, 62-67,67-72, 72-77, 77-82mm)· Include Step Down Filter Adapter Ring Kit(49-37, 52-49, 58-55, 55-52, 62-58, 67-62,72-67, 77-72, 82-77mm )· Great tightness,no wobbling or cross-threading. Ultra-low chemical residues, attached to a solid!· Converts the thread size of your lens to the thread size of any other accessory (such as filters, hoods, flashes and lens converters).· Special aviation aluminum alloy, high strength, impact resistance, twist and pressure.