Serial number 45303 was stamped on December 31, 1930 and cleared final inspection on February 21, 1931. As this guitar was made after April 1930 it has a belly bridge and retains the small OM pick guard that wasn't replaced by the larger size guard until March 1931.
The tuners are Grover #89 Deluxe banjo pages.
Style 28 features:
Back and sides: Brazilian rosewood
Top: Red spruce (Adirondack)
Back stripe: Zig-zag purfling
Other period features:
Ebony belly bridge
Ebony bar neck reinforcement
1-3/4" neck width at nut
25.4” scale length
Tortoiseshell celluloid pick guard (small OM pick guard)
Slotted square and diamond fingerboard inlays
C. F. Martin stamp on back of headstock
No style stamp