Sigma Teleconverter TC-2001 Brand_Feiyu-Tech this feature allows you to

this feature allows you to control exactly when and where the flash is enabled

a new Aspherical Extra-Low Dispersion (ASP/ED) element is paired with traditional AS

built-in DSP (Digital Signal Processor) blocks that achieve quicker and more precise AF performance

creative inclination

Sigma Teleconverter TC-2001 Brand_Feiyu-Tech this feature allows you toEquipped with 2 SLD (Special Low Dispersion) glass element for maximum image quality, the new Sigma Global Vision teleconverters utilize a splash and dust proof construction for long lasting durability. Created exclusively for the Global Vision lenses, these teleconverters ensure the utmost in compatibility, even for large diameter lenses. With effective AF at F8 and 2x the reach, get the most out of your Sigma lens. Usable Lenses and Combinations