Do you mean that you want two white LEDs with a flasher circuit built into them that alternately flashes them like for ditch lights? There's no such thing available, as near as I know. What you're going to need is an alternating flasher circuit that can have LEDs connected to it.
For flashing white LEDs, but not automatically alternating, check http://www.moreleds.com
LED's in general have been a big disappointment to me and maybe i am the problem but i have gone back to using globes and it is working for me. I have red crossing flashing lights (globes) and i bought them on ebay with some other stuff and it was a bargain.
Rgds Ian
Found a person that supplies Walthers and they will work. On there web site it does not show they have them so I called anyways and BOOM they do. I just need flashers (really wated wig wag style like ones on MOW). Give her a call she is great!
Shelly JamisonEvan Designshttp://www.modeltrainsoftware.com/303.410.1118
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