Five Star Manufacturing Battery Heater Pad Style 8.5 x 11.5

Features & Benefits:

• Dimensions 8.5"" x 11.5"" 
• 120 volt;  60 watts
• Silicone covered; acid resistant; pliable
• Fits most car and truck batteries

If bottom of battery box is perforated with holes or has a waffle bottom use a sized piece of sheet metal or sheet aluminum between bottom of box and battery heater.