Lexus CT200h Owner's Manual page 507

NOTICE

When adding coolant
Coolant is neither plain water nor straight antifreeze. The correct mixture of
water and antifreeze must be used to provide proper lubrication, corrosion
protection and cooling. Be sure to read the antifreeze or coolant label.

If you spill coolant
Be sure to wash it off with water to prevent it from damaging parts or paint.
CT200h_OM_OM76067E_(EE)
4-3. Do-it-yourself maintenance
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