Fits all ThermoFlask® Chug Lids and Spout Lids.

Two BPA free O-Rings are included in the pack.

One large O-Ring fits inside the lid.

The smaller O-Ring fits in the drinking spout cap.  

If your lid has a fitting for a straw, check here 

O-Ring installation instructions

Note: This item ships via USPS First Class Mail.