Kevin.Murphy Straight.Defence. This weightless heat protecting straightening balm contains kakadu plum extracts, chitosan derived from sea shells, and Kevin Murphy X-HP Complex™ for heat protection, providing unrivalled defence against the intense heat generated by modern appliances while delivering impressive style hold. The product offers X-treme Heat Protection, protecting hair at temperatures up to 428F. Ingredients... Key ingredients.. Flexan, chitosan, vitamin B5 panthenol, wheat amino acids.