NGK plugs on my series 2a have three things!

Hi, I just looked at my spark plugs, and to my astonishment, they have three contacts, (well technical!). I have never seen plugs like them! i put them back in now, and can't remember what type they were... they looked a little covered in bits, but ok! what are they, I can't find any info on them. They are NGK ones tho. Thought I could do with some spares, but now I don't know what to get! 2 and quarter litre engine 109. Cheers.

just get std plugs

duz it look like this?....

Well, yes, but three of them rather than two! why are they different?

Some combustion chamber designs (such as a rotary motor) require that the spark plugs have the ground electrode placed to the side of the center electrode rather than below as on a traditional plug (see photo). This firing tip design tends to erode the tip of the ground electrode faster than a traditional plug. Erosion at these points creates a larger gap between the center and ground electrodes, causing plug misfire. Thus, by having more ground electrodes, you extend plug life. It is important to note that multi-ground does not mean multi-spark, there will still only be one spark at a time. Therefore, a multi-ground plug will not perform any better and may actually perform worse than a traditional plug, unless the engine is designed for a multiple ground plug.

Cheers for that info, they seemed to have lasted pretty long, so far, they still look alright, I was just checking, as my engine seemed to be performing badly just after cleaning and servicing my zenith.. then noticing the tappets are about as noisy as a riverdance performance, and thought I might as well check the sparks too.. Think I will get some normal ones though... is it the standard BP6ES?
I do like the look of these ones though.. freaked me out a bit at first though.. I thought they had mutated!! haha.