A weight cartridge, positioned behind the face, allows fitters to adjust the swing weight of the S55. It's softer than the weights found in the S56 irons, which helps to create a softer feel at impact, according to Ping.

A weight cartridge, positioned behind the face, allows fitters to adjust the swing weight of the S55. It's softer than the weights found in the S56 irons, which helps to create a softer feel at impact, according to Ping.