Add-WebConfigurationLock to set

Hello, Thank you in advance for your time. i am trying to set <staticContent lockAttributes="*"> using powershell. 

i tried following command. instead of <staticContent lockAttributes="*">  it is setting <staticContent lockAttributes="defaultDocFooter,isDocFooterFileName,enableDocFooter">

Add-WebConfigurationLock -pspath 'MACHINE/WEBROOT/APPHOST/Default Web Site' -filter "system.webServer/staticContent/@*" -type "inclusive" 

any input is greatly appreciated. 

Thank you