 Thus, early versions of the lMG 08 deleted the muzzle booster, although later versions of the lMG 08, and its replacement, the lightened-receiver LMG 08/15 model which reduced the cooling barrel's diameter to just 92.5 mm, changed to a less-heavily perforated barrel shroud which could handle a muzzle booster, as it was realized that with the airflow over an aircraft-mounted machine gun, the fifty-percent-plus amount originally removed had been excessive.The World War II-era German MG 42 was another such machine gun which also made use of a muzzle booster.This application has largely fallen out of use as modern machine gun design switched to delayed blowback and gas operation in many cases.