HG Car Windscreen De-Icer Spray 500ml Works Remarkably Quickly and Effectively. HG Windscreen De-Icer removes snow and ice from windscreens very quickly and effectively. Even heavily frosted windscreens are defrosted quickly. Scraping is no longer needed and driving off with poor visibility, which creates life-threatening situations, is a thing of the past. HG windscreen de-icer also prevents rapid re-frosting. Size: 500ml. Directions for Use: Very thick layers of snow should be brushed off before using HG Windscreen De-Icer. 1. Turn the nozzle on the front a quarter turn to open.