America's original pre-packaged concrete pump primer, Prime-A-Pac is the first choice among line pumpers for its oatmeal-like consistency that works on long runs, rubber hoses and difficult set-ups. Just one pail of this bentonite clay-based formula replaces 18 - 94lb. bags of Portland Cement. Prime-A-Pac quickly thickens so that you can prime upon arrival at the jobsite and it is the closest substitute for cement slurries. Not for use in structural concrete. It is available in 2lb. bags. 18 bags per box or pail.