For sale is this 1 pc of a Modular boring reducer extension. I think this is a Kaiser, as I had a lot of other Kaiser, or Big Kaiser extensions that I sold, and this was with them. But, I can not see the markings on this, so I'll take many pics and try to give you the sizes.

On the larger dia end, the largest flange dia is about 2.990" dia, The shank dia is about 1.416" dia, or about 36MM and about 1.580" long up to the 2.990 dia flange. The pin hole dia on that end by the ID threads is about .198" dia.

 The sliding cross pin is about .546" dia, and slides thru the 1.416" dia and sticks out about .31" on each side .

 I think the ID end threads are left hand, and have a minor dia of about .631", or 16mm. So, I think they are a LH metric thread. I do not have LH gages to figure out the thread size. possibly an M18 x 2.0, as it looks course..?

The long, reduced extension end is about 1.220" dia and about 3.1" long to the 2.990" dia flange. the dia of that ID hole on the very end is about .701", the ID across those flanges is about 1.006"

Write me if you need any other sizes,

Thanks, have a good day!