Malaysian Clothing

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These street pics show you what people wear day to day

https://www.google.co.id/search?rlz=1C1 … 2UlMfgASkA

For mild class, look here

https://www.carlist.my/news/kl-city-gra … ong/16881/

Arabic kit is uncommon except in mosques so you'd get funny looks and no street cred.
Looks like a good pair of trousers and a decent shirt is your winner, but skip the tie for general wear.
There are plenty of good tailors that'll knock out made to measure shirts for you.

Thank you, I learned a new search term to use in the future to boot. I appreciate the help 

Assuming I found the correct pictures of you, you're going to have trouble finding off the peg shirts so a tailor is a must.
Plenty around and not expensive.

Since you're not Muslim I would avoid Arabic clothing, I am Muslim and have still been questioned regarding wearing it. Once the person questioning knew I was Muslim no problem. And as was mentioned earlier it's typically only worn on Friday go to/from the Mosque that you see such dress.

I wear regular button up shirts and dress pants most of the time. I brought the pants from the US, but have had the shirts tailored for my size (I'm a BIG guy by local standards - nothing off the shelf).

@iskandarhack: I wasn't looking to wear religious attire. I was looking to wear some comfortable robes that would be considered business formal.

@Fred: I'm well aware that SE Asia does not make anything in my size off the rack (lived in Thailand for over a year), no matter how skinny or fat I get. I wasn't looking for street cred, I was looking to get away with wearing outdoor pajamas.

When not working I wear pajama type pants that are tailored to look a little like dress pants, often with a V neck t-shirt. In this heat I understand.