The S4Z08B062-44P is the most efficient vibration motor we offer.  It draws a remarkably low current of 9 ma (typical) @  3 Vdc while generating a vibration force of 0.75 Gpk.   Energy consumption is a mere 27 mw.  If you require this motor without the rubber boot order S4Z08B062-44P.   Custom lead wire lengths are available as are connectors.    This series of  low current vibration motors are relatively high priced.  After sample approval, the minimum order is 1 master carton of 3520 pcs @  USD  2.15 ea