The Sunpak St Up 37-46 Step Up Ring is a high-quality accessory designed to allow accessories with a 37mm thread diameter to be used with lenses that have a 46mm filter diameter. This step-up ring is made from durable materials to ensure a secure fit and optimal performance. It enables photographers to expand their creative options by enabling the use of various filters, lens hoods, and other attachments on lenses with different filter thread sizes. The Sunpak St Up 37-46 Step Up Ring is a versatile and essential tool for any photographer looking to enhance their photography equipment setup.