Tool id

[wantacoe]

Anyone know what this is? Both ends are 1/2". Onlyh markings are 599 569. Thanks

 

[ETJ]

 

[wantacoe]

ETJ, Thank you.

 

[KnurledNut]

That was a Caterpillar socket used on dozer drain plugs. I think I still have one somewhere. And whoever took that picture and description above can't read a tape measure. The sizes of those was 15/16 and 1-1/8.