This Piece BHP-21 - Headset parts - BBB can function as a stem raiser , or Instead of a Star Nut.

I got one as a stem raiser, Its a 1" Quill with a Bolt , Hex socket + internally threaded, so once the wedge is tightened ,

a 6mm Bolt thru the stem cap works as Usual . for threadless headset adjustments ..

So you can leave all the shim spacers off and put all of the Quill inside the fork steerer.

It went on this Bike (bought Used , factory sawed off fork steerer too short for My fit.) WB Bicycle Gallery: Robert Clark's Koga Miyata WTR