All HOWW Thermal Tumblers (sonic seal) are guaranteed to last a lifetime under normal use.

Howw Thermal Plastic Glassware are top rack dishwasher safe. But hand wash is recommended just because dishwashers are pretty tough on plastic products.

Should the tumbler becomes defective at the sonic seal (where the two glasses are joined) then simply send it back prepaid and we will provide a replacement.

Send defective glass to:

Howw Manufacturing
Attn: Returns
28W020 Commercial Ave
Barrington, IL 60010

Be sure to include your return shipping information and any special instructions.

This Guarantee does not cover:

Mis-use, including but not limited to; dropping causing cracking, commercial dishwashers, intentional breakage of the seal.

Dishwashing soaps or hard water conditions that that cause discoloration to the tumbler.

Returning after use for events when no defect is present or intentional damage has been done.

Slider lids are not covered under this guarantee.