S tanley is recalling approximately 2.6 million of its switchback and trigger action stainless steel travel mugs sold in the U.S. because of a potential burn hazard. The company said that the mug’s lid threads can shrink when exposed to heat and torque, causing the lid to detach during use, posing a burn hazard.

Stanley is recalling 2.6 million mugs sold in the U.S. after the company received dozens of consumer complaints, including some users who reported getting burned and requiring medical attention.