1" x 0.25" (wide thickness) x ~1.5" length    wedge cross-section;  end is blunt/squared off (NOT beveled)
Wedge motor brush for Century 1.5hp repulsion start (induction run) motor - for start commutator.
This  brush is used/ original (still has ~1.5" length)
Worked fine in 1920 Century Orgoblo pipe organ blower.
One picture shows the wedged end, 1/4" is the thick edge.
Brushes are wedged so adjacent commutator contacts are not shorted.
Original brush shows normal copper slug/sleeve as a part of the brush before the graphite portion commences.
INSTALLATION: Repulsion start brushes are replaced/swapped by significantly pulling back (copper?) leaf spring in order to allow clearance for the length of the brush to slip in/out of the rectangular (really wedged) brush holder slot.  The leaf spring pushes the brush against the commutator contacts during start until the shaft reaches "escape velocity" at which time a centripetal mechanism pushes the brush assembly away from the commutator (by maybe 1/8", not that much)
Please inquire about expedited shipping (next-day etc)
See also other ebay item that is a PAIR of wedge brushes.
Note that often ONE BRUSH wears down completely leaving its paired twin with years of service remaining.
Thus this brush could replace the worn brush by cutting the shunt wire and connecting the replacement brush (we recommend soldering and heat shrink spaghetti insulation for the center section)
Inquire about expedited shipping.