Kia Optima Stepwell Bulb Size

Additional Notes

• The Kia Optima uses the 12961 bulb across all listed model years for the stepwell position, making it the sole bulb type present in these specifications.
• The 12961 is a Philips part number designating a miniature wedge bulb in the T10 form factor with a W2.1x9.5d base, rated at 12 volts and 5 watts.
• The T10 designation refers to a tubular bulb with a width of 10 millimeters, commonly used in low-current interior lighting applications such as stepwells, courtesy lights, and instrument panels.
• The W2.1x9.5d base is a wedge-type base, meaning the bulb is held in its socket by the tension of the glass envelope itself rather than by a separate metal cap, which is a standard fitment method for low-wattage interior bulbs.
• At 5 watts and 12 volts, the 12961 draws approximately 0.42 amperes, consistent with the low power demands typical of interior courtesy lighting circuits.
• The 2006 model year carries a production date qualifier of "From 12/1/2005," indicating that this specification applies only to vehicles produced on or after that date within the 2006 model year.
• The 2010 model year carries a production date qualifier of "To 9/18/2009," indicating that this specification applies only to vehicles produced on or before that date within the 2010 model year.
• The production date qualifiers on the 2006 and 2010 entries signal mid-cycle specification changes within those model years, and fitment should be confirmed against the vehicle's production date rather than the model year alone.
• The 2007-2009 model years carry no production date qualifiers, indicating the 12961 bulb applies to the full production run of those years without restriction.