Use these slightly translucent row covers (now .8 mil.) in northern and cooler areas for better temperature control. Plant crops 10 or more days earlier. Promotes earlier maturity and higher yields in tests. Reduces wind damage. Daytime temperatures under these covers are elevated an average of 10 to 30°F, for better crop growth. The slits remain open during the day for ventilation in extreme heat, closing at night for heat retention and frost protection (1-4°F). Harvest crops up to 2 weeks earlier than normal. The use of the 05042-00-00 Wire Tunnel Supports is recommended.