Indicator bag has one clear side and one white side and contains a blue gel which turns pink when saturated (It cannot be regenerated). Regenerable bags have two sides of white Tyvek and may be regenerated and reused continuously. A card is included in each pack which will change from blue to pink when the bag is saturated and requires regeneration. Each bag measures 3 x 3 x 1/4" and can handle a container volume up to 2 gallons (476 cubic inches).