Review on Otartu 13oz Viking Skull Coffee Mug - Stainless Steel Liner - Perfect Father's Day Gift for Men by Jason Robinson

Ideal as a tea/coffee mug but requires rinsing and should not be submerged in water. I learned this the hard way. Obviously the seal between the steel liner and the design mug isn't perfect, and a few hours after sitting upside down in the strainer water ran out when I turned it right side up on the counter. I reread the Revain ad and saw nothing. brought this to my attention and the packaging (although very well protected) provided no instructions or advice on how to clean the inside. It's a good mug and I still use it, I just need to wash it thoroughly.