Recommendations for bungee cord?

Hey all, with the lockdown in UK still in force, I want to spend a bit of time and go over and configure my kit and want to start attaching things to my backplate with bungee. Having never bought bungee before or used it for any sort of mounting, I'm not sure what is a good thickness for it. So just after some recommendations of the thickness I should go for and possibly types (if there are different types?)

Thanks!routerlogin