I need some advice please and thanks 

I have a Dell switch N4032 And a Dlink switch. 

On the Dlink switch I have created a trunk port on VLAN id 300 and a lag group containing 2 ports. 

On the Dell switch I have created a

VLAN 300.

Set ports 23/24 to trunk vlan300

Set lag settings to po1 300 pvid

Gone to VLAN membership, selected the vlan300

On the lags I have U which I assume is untagged both for static and current.

On the ports, I have static and F for current.

I am not sure why the F is present, can someone provide some guidance.