Which is the best heat protecting spray for flat ironing?

The best heat protector is Pro Naturals Moroccan Oil Hair Treatment with Heat Protector, it helps strengthen the hair that's prone to breakage, splitting or snapping off, gently smoothes the hair and form a protective mist on surface against heat damage, reduces Frizz and helps prevent further damage, leaves hair healthy, shiny and resilient and provides heat protection against electronic hair tools. You must use it after you use the straightener. Check it out at http://www.rylees.ca  . Hope it helps.

Alberto Vo5 makes a heat protectant spray called Miracle Mist Heat Defense Conditioning Spray.You can find it at most local drugstore chains like CVS or Walgreen's. Walmart usually carries it as well and you can get it for less that $5!

One really good choice is the Beyond the Zone Turn up the Heat protection spray which sells for $7.49.  Beyond The Zone Turn Up The Heat Flat Iron Protection Spray is a spray-in treatment that smooths hair. This humidity-resistant heat styling aid adds a "Heat Defense" barrier that protects the hair from thermal heat. Beyond The Zone Turn Up The Heat Flat Iron Protection Spray helps optimize the effectiveness of flat irons, curling irons, and hair dryers while providing outstanding heat protection, and adding smoothness, shine, and softness to your hair..  Beyond The Zone Turn Up the Heat Serum protects hair from heat damage caused by heat styling tools. Leaves hair soft, shiny, and healthy-looking.  Another is the Silk Elements Megasilk Olive heat protection spray which sells for $5.99.  Silk Elements Megasilk Olive Heat Protection Spray is formulated with Olive Oil and Silk Protein, helps protect the hair from damage caused by heated appliances. Leaves hair soft and silky while providing a luxurious shine.