Prop Agitator WHATCOM MANUFACTURING, INC. has been producing quality built slurry agitators for over 18 years and continues to add new models for all types of applications. Our electric motor drive prop agitators have been installed at many dairies where maximum agitation using minimal horsepower is a concern. HEAVY DUTY CONSTRUCTION Square tube stems with internal grease lubed bearings for long life and trouble free service. Next >>