Amika Blockade Heat Defense Serum – 1.7oz is your first line of defense against heat damage. This lightweight serum shields hair from thermal styling up to 450°F while sealing in moisture and smoothing frizz. Infused with sea buckthorn and nourishing vitamins, it protects without buildup, leaving your strands silky, shiny, and safeguarded — whether you’re blow-drying, straightening, or curling. Ideal for all hair types.