MB make specific covers for the SLK R170 & R171 in Japan, perhaps they do too in your neck of the woods. Bit expensive but tailor made to fit, 3 different types of materials are used (3 types of covers) very soft & won't scratch, very light weight material like wind breaker, very stiff & waterproof.
I also have a R171 cover that was given to me & it also fits the R170 no problem.
I would be careful about the type of material you choose for the cover if it's going to be outside, when it's windy & you get dust on the car, the cover could mark your clearcoat if it's the hard type cover.
Anyway..hope this is useful to you.
This cover from Park Place is fantastic. I bought one over a year ago for $184 but I notice the current increase in price.
For 3 weeks while I was abroad my car and cover was subject to the elements from blazing sunshine to rain, dust, leaves and even bird droppings. It just took a gentle wipe with a damp cloth and was as good as ever. But more importantly, the car was clean and ready to roll.
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