How long can the tumbler keep drinks cold / hot？
Can retain ice cold for up to 24 hours and warm beverages around 6-8 hours with double-wall vacuum insulation.
Is the tumbler leakproof when using the straw lid？
The flip lid is splash-proof for daily carry; avoid full upside-down long-time flipping for zero leakage.
Is it microwave safe?（Clear Glass Cups）
Not recommended for microwave; ideal for cold brew, iced coffee, juice only.
What size straw do these toppers fit?
Designed to fit most common 8mm-10mm standard straws for tumblers & glass cups.
Will the silicone deform after long-time use?
Flexible silicone material resists aging, no deformation with daily frequent use。
