Question about SANDISK Extreme PRO

I would buy this key because of its high speed. Does using a USB-C adapter reduce the transfer speed? I have a MacBook Air 13 (2018). Thank you J'aimerais acheter cette clé pour sa grande vitesse. Est-ce que l'utilisation d'un adaptateur USB-C va faire baisser la vitesse de transfert ? J'ai un MacBook Air 13 (2018). Merci