Vietnamese D2C brand Coolmate has secured $6 million in Series B funding led by Vertex Ventures.The funding will accelerate Coolmate's international expansion, product innovation, and omnichannel retail presence across Southeast Asia.Coolmate, founded in 2019, has been successful in ecommerce sales across major online marketplaces.The brand focuses on providing durable, stylish, and comfortable clothing for modern consumers while reducing the environmental footprint.