If you've been seeing Stanley Quencher posts on every celebrity's Instagram and wondering why everyone's buying a water bottle, Stanley's Summer Kickoff Sale has an answer: the viral 40-ounce tumbler is now 25% off.

The sale runs through May 24, and the entire collection—including the iconic 40-ounce Stanley Quencher H2.0 FlowState Tumbler—is 25% off sitewide. The 40-ounce tumbler drops from $45 to $33.75.

The Stanley Quencher has become a status symbol among celebrities and fitness enthusiasts. Double-wall insulation keeps drinks cold for 40 hours. The rotating lid has three positions: straw opening, wide mouth, and full cover. It fits in car cup holders.

The 30-ounce version drops to $30 from $40 and keeps water cold for 9 hours.

Colors and sizes are selling out quickly. If you've been considering buying one, Memorial Day weekend is the time. Popular colors won't last long.