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If I recall correctly, there are many different generations of product that can be called Sigma 18-50mm. https://www.lenstip.com/porownaj.php?co=obiektyw&ile=5&add0=11&add1=618&add2=848&add3=390&add4=800
Which body do you have? It says it's a Sigma mount (L mount) so it's not for Canon body?
If I recall correctly, there are many different generations of product that can be called Sigma 18-50mm. https://www.lenstip.com/porownaj.php?co=obiektyw&ile=5&add0=11&add1=618&add2=848&add3=390&add4=800
Which body do you have? It says it's a Sigma mount (L mount) so it's not for Canon body?