Stens 120-178 Single Primer Bulb Replaces Briggs & Stratton 694394 4178 5084D 494408 4128 Primer bulb replacement Stens part number 120-178; or small engine outdoor power equipment Replaces Briggs and Stratton 694394 4178 5084D 494408 4128 Not compatible with greater than 10-Percent ethanol fuel