A. Action Frame.
B's Indicate the Cushions, or Bushing, of felt, cloth or leather.
C. Balance Rail.
D. Balance Pin. Round.
E. Mortised Cap for Balance Pin. Bushed.
F. Key.
G. Lead.
H. Back Check.
I. Bottom or Key Rocker.
J. Bottom Screws; used to regulate height of Jack.
K. Jack.
L. Jack Spring; concealed under Bottom.
M. Center Pin to Jack.
N. Hammer Rail.
O. Regulating Screw.
P. Regulating Button.
Q. Flange Rail.
R. Flange. Split.
S. Flange Rail Screw.
T. Flange Screw, to regulate jaws of flange.
U. Hammer Butt.
V. Center Pin.
W. Hammer Stem or Shank.
X. Hammer Head.
Y. Hammer Felt. Treble hammers sometimes capped with buckskin in old instruments.