what gauge extension cord for generator

{"cid":"91181013","title":"Universal Generator Auto Retractable Extension Cord Reel , Flexible Power Cable","imgUrl":"https:\/\/img.silkroadsl.com\/nimg\/83\/5d\/93602c5aae8a60a81ac321ba411d-200x200-1.jpg","attrs":{"Price":"Negoation","Brand Name":"SFC","Model Number":"SFC-GFCI-02","Minimum Order Quantity":"100PCS","Delivery Time":"25Days","Certification":"ETL","Place of Origin":"Jiaxing,China","Payment Terms":"T\/T, LC","Supply Ability":"10000PCS Per Month","Packaging Details":"every one into plastrics poke and box. 5pcs into paper CTN.","Material":"ABS , PA66 UL94V0","Rating":"20a,125vac, 30A 125VAC","outlet quantity":"20A 125VAC GFCI duplex outlets","Color":"Black|Yellow","Power Cord Length":"15 ft","Cord":"UL approved 10AWG"}}

{"cid":"91220380","title":"5 in 1 Generator Adapter Extension Cord NEMA L14-30P to Four 5-20R \/ 5-15R & L14-30R 30A 250V RV Power Adapter","imgUrl":"https:\/\/img.silkroadsl.com\/nimg\/56\/74\/c567acfa23090b9ae2107b0265b3-200x200-1.jpg","attrs":{"Price":"By Specifications","Brand Name":"HENG-WELL","Minimum Order Quantity":"50PCS","Delivery Time":"28 days","Place of Origin":"SHENZHEN","Certification":"UL","Packaging Details":"Negotiable","Payment Terms":"T\/T \uff0c Large quantities can be negotiated","Supply Ability":"5000 Pieces per Month","Product Name":"Nema 5 In 1 Generator Adapter Extension Cord","Voltage Rating":"125V 250V","Warranty":"1 Year","Connector Type1":"NEMA 14-30P","Connector Type2":"NEMA 14-30R+ 4* 5-15R\/5-20R","Length":"1.2M\/1.5M\/1.8M(OEM)","Material":"PVC Jacket Pure Copper","Wire Gauge":"10AWG\/4C"}}