Asda are selling this in 4litre tubs, price is ok but main factor is it works to minus 10 centigrade! allowing for windchill factor means should not get frozen nozzles.
asda's own stuff does not give temp, just says may help prevent freezing
Prestone® De- Icer Windshield Washer Fluid De-Icer with Dirt Blocker is specifically engineered to improve winter driving visibility. Using Prestone® De-Icer Washer Fluid helps clear light ice and frost and helps prevent dangerous re-freeze from forming on your windshield. Our Dirt Blocker formula improves your total winter driving visibility by helping to repel the build-up of dirt and salt from road spray as you drive. Get clearer glass and enhanced visibility for longer periods of time.
Use at full strength. Add directly to washer fluid resevoir. Make sure to wash exposed skin thoroughly with soap and water after each use.
De-Icer’s high methanol content ensures strong ice melting power and the addition of ethylene glycol helps prevent dangerous re-freeze from forming on windshields.
Prestone’s Dirt Blocker technology coats windshields with a resilient organo-modified siloxane copolymer. This formulation imparts a durable hydrophobic surface on the windshield that helps prevent road spray from adhering to windshield glass by moving dirt particles away from the windshield surface and into the washer fluid that beads and rolls off the glass.