Comparison of Canon Extender EF 1.4x III and Sigma TC-1401 1.4X Teleconverter

Attribute	Canon Extender EF 1.4x III ×	Sigma TC-1401 1.4X Teleconverter ×
Notes	-	Dust and splash-proof; Available AF Mounts: Canon EF, Nikon F, Sigma SA
Weight (g)	225	190
Type	Teleconverter	Teleconverter
Brand	Canon	Sigma
Name	Canon Extender EF 1.4x III	Sigma TC-1401 1.4X Teleconverter
Lens Construction	7 elements in 3 groups	7 elements in 5 groups, including 1 SLD element
Image Circle	35mm	35mm
Magnification Ratio (x)	1.4	1.4
Diameter (mm)	72	69.8
Focal Length Multiplier	1.4X that of the master lens	1.4X that of the master lens
Effective Reduction in Aperture	1 f-stop	1 f-stop
Length (mm)	27.2	25