If you're replacing the hose because it's too short, get a coupler Coupler: Joins LP Reg Hoses w/ 3/8-Inch Fittings and add the appropriate length hose to make up the difference.
Hi couv, the accessory that you linked is an adapter, It's used to adapt different thread size. For example old 1st stages came with 3/8" in the HP ports. Modern SPGs come with 7/16" thread, so you need an adapter from 7/16 female to 3/8 Male.
It's not coupler to enlarge a short hose.