Comparison of Nikon AF-S TC-20E II 2X and Tamron 2X TC-X20

Attribute	Tamron 2X TC-X20 ×	Nikon AF-S TC-20E II 2X ×
Type	Teleconverter	Teleconverter
Name	Tamron 2X TC-X20	Nikon AF-S TC-20E II 2X
Weight (g)	360	355
Image Circle	35mm	35mm
Brand	Tamron	Nikon
Magnification Ratio (x)	2	2
Lens Construction	9 elements in 5 groups, including 1 Low Dispersion element	7 elements in 6 groups
Notes	Available AF Mounts: Canon EF, Nikon F; Included Accessories: Mount cap, Rear cap, Lens case	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.
Diameter (mm)	69.8	66
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)	53.6	55