The USED Sigma Tele-Macro Multi-coated 2x 1:1 Tube for Pentax is a high-quality lens accessory designed for Pentax cameras. This teleconverter, specifically made for Pentax, allows for a 2x focal length, making it ideal for capturing detailed close-up shots. With manual focus capabilities and a sturdy Pentax K mount, this Sigma lens unit offers photographers a reliable and versatile option for their photography needs.