Men’s and Women’s Machine Gun Kelly Workout Gear in Machine Gun Kelly Merch. Machine Gun Kelly is one of the most popular and controversial rappers in the music industry. With hits such as “In The Club” and “Firing Squads,” MGK has turned heads with his gritty lyrics and energetic performance. If you’re looking to mimic MGK’s workout routine, we’ve got just the gear for you! Shop our selection of Machine Gun Kelly workout clothes and accessories today to get your physique looking just like his!