The BA15s type incandescent bulbs are used extensively throughout many RVs in ceiling fixtures, over counters, in basements, in patio fixtures, and in some reading lamps.

These bulbs are also used externally in automotive tail lights. However, the LED equivalents do not make good tail lights.

The base of a BA15s bulb is grounded and is a metallic 15mm diameter base with symmetric bayonet side-pins. A single contact at the bottom provides a contact for the positive lead.

Typical bulb numbers for this group are the 93, 1073, 1141, 1156, and 1295 whose physical dimensions are

     width 1.0 inches
     length 2.0 inches

The 1003 bulb uses the same base but measures

     width 0.75 inches
     length 1.8 inches

Operating specifications for the standard (omnidirectional) BA15s bulbs are

The nominal version for this bulb found in most RVs is the 1141, using 1.5 amps to produce initially 259 lumens, degrading to 104 lumens over the life of the bulb.

Bulb numbers 93 and 1003 are lower power versions of the 1141, using around 1 amp to produce a maximum of 189 lumens.

The 1156 is typically found in many automotive tail-lights and is used in many RVs to provide a brighter bulb than the 1141. However, it comes with the cost of more power and higher temperatures. The 1073 is an equivalent bulb used in some environments.

The 1295 is found in the "scare lights" recently introduced on many of the toy-haulers in the southwest desert. It is power hungry and uses 3 amps to offer the highest luminosity of 629 lumens. However, within the expected lifetime of 200 hours, it will quickly drop to a luminosity of 251 lumens, less than an 1141.

See donsbulbs.com for detailed specifications of the bulb you are replacing.