10 mm cable

[steptoe]

Hi everyone how can i tell the difference between 6mm and 10mm T+E cable
I have some T+E 10 mm tower clips and they don't fit that snugly, 2mm side to side movement when placed over the cable
Any help to identify the differences would be appreciated

 

[steptoe]

Many thanks for replies
found some 6mm single strand earth and used it has a gauge it was very slightly larger than earth in T+ E and noticeably smaller than L and N