what is dk yarn

{"title":"Custom 8s Soft Cotton Lightweight Denim Fabric Double Core Yarn 180 cm","imgUrl":"https:\/\/img.silkroadsl.com\/nimg\/91\/84\/cd38773c2e0168ac32c7c34e1a2f-200x200-1.jpg","attrs":{"Price":"$1.5-$2.0","Brand Name":"TianSL Textile Co., Ltd","Model Number":"ZX1003#","Minimum Order Quantity":"3,000 Meters","Delivery Time":"10 days","Certification":"CMA\\CNAS\\ilac-MRA\\FCL","Place of Origin":"CHINA","Payment Terms":"L\/C, T\/T","Supply Ability":"200,000 meters","Packaging Details":"International Packing Standard","Composition":"75% cotton 23% polyester 2% spandex","Width":"180 cm","Weight":"10.6 oz","%22 Specification":"8+8*16\/40+16\/70","Post finishing":"Desizing","Color":"Black \/ Indigo \/ Dark indigo"}}