According to the DOT code on the tire, Rovelo are made by Sailun. Sailun originally started with transport and heavy equiptment tires, and have now got into the passenger tire market. They are pretty decent tires and are leaps and bounds better than other chinese brands, like Wanli etc.
Walmart is a reputable retailer, and would not sell sub-standard tires. Also consider that Walmart gives a nationwide warranty on any tires you buy from them, give you free rotations every 10,000km(and balancing if required), free flat repairs (thats $20 right there), and a road hazard warranty.
Most of the Rovelo tread patterns are identical to the Sailun branded tires, so you will find more reviews looking for those. The Rovelo snow tires are identical to the Sailun Ice Blazer, and that tire has gotten good reviews.
Cooper tires makes them
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