Review on 1156 LED Light Bulb Replacement for RV Trailer: 1141 93 P21W 67 12V 💡 35W Halogen Bulb, BA15S Single Contact Bayonet, 2.5W 330lm, Daylight White 5000K - Pack of 4 by Keith Baker

Do not buy this if you have a Saab 9-3 and expect it to work plug and play as advertised. While they will fit and work in place of the P21W for taillights, they will flash every 5-10 seconds when your vehicle is off. This is because they require some sort of load resistor to work, although this is not mentioned in the product description as the product is primarily advertised as a replacement. Also, only three of the four that came with it worked... I'm giving them two stars because they seemed pretty solid. They might work for you if you know what you're getting into, but the description is misleading. Also in my case one of the four broke straight away (tried the other two first and they were fine so not that I screwed up...)