WorkVenture gives you an inside look at what it's like to work at Mastery Metal Factory Co., Ltd., office & team photos, reviews and more. This is the Mastery Metal Factory Co., Ltd. Company Page. All content is posted anonymously by employees currently or previously working at Mastery Metal Factory Co., Ltd..Apply to Dumex LimitedApply to Show No LimitApply to CentureApply to WorkVenture Technologies