Can anyone ID this attachment?

[Kscardsfan]

We found this cleaning out my wife’s grandpas shop. We’re trying to determine what it attaches to. He was a carpenter and woodworker his whole life. Thanks guys.

 

[The Cobbler]

I'm thinking a router fence with vacuum port

 

[PCustoms]

I'm thinking a router fence with vacuum port

Yep

 

[Meursault74]

I'm thinking a router fence with vacuum port

I was thinking the same.

 

[Lwel9226]

I'm thinking a router fence with vacuum port

My thoughts....

LynnW

 

[RTM]

Me too