Abstract: A push-in bulb base for use in a bayonet-type bulb socket. The push-in base does not require turning of the bulb base to engage the retaining bayonets of the bulb base in the L-shaped retaining slot of the bulb socket. The push-in bulb base has integrally formed flexible retainers which flex inward during installation and then flex back to their normal position to engage the L-shaped retaining slots of the bulb socket. An integrally formed alignment rib prevents the bulb base from being inserted into the bulb socket in a position that would prohibit the engagement of the retainer with the L-shaped retaining slot.