FYI: Inside tumbler it is water spots not yet dried, not stain. Tumbler clean and stain-free. Contigo AUTOSEAL West Loop Stainless Steel Travel Mug, 16 oz, Key item features: Lids are sealed - AUTOSEAL technology is Leak and spill proof. For the long Haul - drinks stay hot up to 7 hours and cold up to 18 with THERMALOCK vacuum insulation. Lend a hand - easy one-handed drinking with the push of a button; Easy to clean - easy clean lid completely opens for an Extra clean with no separate parts to take apart or misplace. Lock it up - AUTOSEAL button lock for added peace of mind; Perfect fit - Fits most car cup holders and under most single serve brewers. Clean up - top rack dishwasher lid, hand wash body.