Comparison of Olympus EC-20 2X Zuiko Digital and Sigma TC-2001 2X Teleconverter

Attribute	Sigma TC-2001 2X Teleconverter ×	Olympus EC-20 2X Zuiko Digital ×
Type	Teleconverter	Teleconverter
Name	Sigma TC-2001 2X Teleconverter	Olympus EC-20 2X Zuiko Digital
Weight (g)	290	225
Image Circle	35mm	Four-thirds
Brand	Sigma	Olympus
Magnification Ratio (x)	2	2
Lens Construction	10 elements in 5 groups, including 2 SLD elements	7 elements in 5 groups
Notes	Dust and splash-proof; Available AF Mounts: Canon EF, Nikon F, Sigma SA	Can be attached to any ZUIKO DIGITAL interchangeable lens. Dust & Drip Proof. Included Accessories: Lens Cap (BC-1), Lens Case (LSC-0814).
Diameter (mm)	69.8	68
Focal Length Multiplier	2X that of the master lens	2X that of the master lens
Effective Reduction in Aperture	2 f-stops	2 f-stops
Length (mm)	48.9	41