What is Lug ?
Lug is (verb) to carry or pull something heavy I had to lug my cases up two flights of stairs. Lugging those boxes up into the attic has worn me out. (NOTE: lugging – lugged) (noun) a small projecting piece on the side of something such as a jar, for carrying it or for attaching something to it One of the lugs on the vase has been knocked off.
source: Easier English, Student Dictionary Upper Intermediate Level