Torx key size? cargo tie-downs

[Trio]

I searched but could not find. Can someone tell me the correct size of the torx head bit / key to remove the D-ring cargo tie downs in the back of my '99 Tahoe? I am going to need to buy one, since the size needed is larger than any torx bits I have on hand. Thanks in advance.

 

[Pinger]

T50.

 

[Trio]

T50.

Thanks!