Comparison of Nikon AF-S TC-20E II 2X and Sigma TC-2001 2X Teleconverter

Attribute	Nikon AF-S TC-20E II 2X ×	Sigma TC-2001 2X Teleconverter ×
Type	Teleconverter	Teleconverter
Name	Nikon AF-S TC-20E II 2X	Sigma TC-2001 2X Teleconverter
Weight (g)	355	290
Image Circle	35mm	35mm
Brand	Nikon	Sigma
Magnification Ratio (x)	2	2
Lens Construction	7 elements in 6 groups	10 elements in 5 groups, including 2 SLD elements
Notes	Compatible with AF-S and AF-I Nikkor lenses except AF-S 17-35mm f/2.8D IF-ED and AF-S 28-70mm f/2.8D IF-ED.	Dust and splash-proof; Available AF Mounts: Canon EF, Nikon F, Sigma SA
Diameter (mm)	66	69.8
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)	55	48.9