A tried a Anco blade on my 97 SL320 and found nothing latched the blade to arm. The blade was setup for arms with a small hole to click into but the SL does not have a hole. A dealer blade solved the problem and blade rubbing the edges of a pillars the Rain X blade had. I think it was ~ $32, but it FITS where the $ 25 aftermarket didn't!

When it came time to change the blade on the 97 C280, the dealer blade was ~ $ 16 when a aftermarket bound not to fit was $ 25. For 97 the W 210 and W202 used the same blades, not sure about your year. Do you have the single wiper like my cars or two? The latch shows fitment and mine had the marking
. 2
. 1
202

The SL blade had 129.