I latest ones I have bought came in a box with 2 rectangular filters. I couldnt even find where they go initially. I assume down under the glove box. My back is sore at the mo, should I even go near this job till thats better??
I wouldn't. You have to work with your head in the passenger footwell looking upwards, remove three small self-taps and then pull out the filters. At this point you get a face full of dust as the filters scrape past the fan housing.
As they are located fairly low down, no need to have that head anywhere near, when you have at last been able to lay on your stomach, after stretching your spine removing those wee self tapping bolts.
Ours I doubt had been replaced for three years when we first bought it, but I did replace them twice, in the four years we subsequently owned her. Not a particularly accessible place to install them really. But worth the effort replacing them: