A quarter-barrel keg, also known as a pony keg, is a popular size of beer keg that holds approximately 7.75 gallons, or 29.3 liters. This size is commonly used for small gatherings, parties, and events, making it a convenient option for serving draft beer without the bulk of larger kegs. The quarter-barrel keg is typically 16 inches in diameter and 14.9 inches tall, making it easier to transport and store than larger kegs like the half-barrel keg. It can serve around 82 pints of beer, making it an ideal choice for social occasions where moderate consumption is expected.