Weekdays open at 7pm, weekends open at 6:30am.
What is nice? The steam lala, hokkien mee, fried kuey tiaw, jagung mantis prawn, indian mee, zhi hun gen and soooooooo many more!
Always crowded there.. be prepared for 45 mins or more of waiting before food is served 
btw i'm the mayorship for Boston in foursquare 

klang have indeed a ground of good food if you really know the places real well. I can assure you if you follow my below guide you will come back for more.
1) Pandamaran stall hawker: You should try the "yoyo ice" bobochacha mix with red bean. It has the smoothest yoyo ice and the taste are supurb. I bring a lot of friend to try and everyone go for second glass. ( If compare this with the yoyo ice that is being sell in the fried chicken cuz fried chicken yoyo ice are sucks.....)
2) Pandamaran famous "cai ge" .....only pandamaran sold it. And trust me not just the cai ge.....they have the best goreng pisang and cucur udang too. The taste are totally authentic......you will get the feel of 1980's feeling.
3) Ah he ba kut teh....the only sell at night ( 5.30pm to 8pm) The fastest selling ba kut teh in klang area. Try it and you will know it.

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If you want seafood....perlama and yong tat is the best choice though if you compare to sekinchan and tanjung sepat....we might not be able to fight.

And also Da tuan Yuan in bukit raja which serve the best steam fish.
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