What type and size of LP gas tank is compatible with this grill?

This grill is designed for use with a standard 20 lb liquid propane gas tank, which is approximately 12 inches in diameter and 18.5 inches high. Never connect the grill to an LP gas tank that exceeds this capacity. The cylinder must also be fitted with an Overfill Protection Device (OPD) and a QCC1 connection. (Pages 5, 6)