Beauty-item bandits with an eye for an expensive coiffure have made off with a suitcase full of hair products after an early morning robbery in Melbourne's northwest.

Police are combing for clues after the two male offenders threw a rock through the front door of an Essendon salon early on Wednesday morning and filled a suitcase with a large number of pricey haircare products.

The duo, wearing face covers, black clothes and gloves, fled the scene in a new-model silver Toyota Corolla and police are still hunting for the bad-hair-day burglars.