From Gibson:

The World-Famous Workhorse

The J-45 is Gibson's best-selling acoustic of all time. Nicknamed "The Workhorse" and first introduced in 1942, this iconic acoustic has become the cornerstone of its round-shoulder, dreadnought line. World renowned for its full, balanced expression, warm bass and excellent projection, the J-45 has been refined to carry this legacy to new heights. The Gibson J-45 Standard delivers a sound with incredible dynamic range, warm mids, and a tight punchy bass.

SPECS

Body
Body Shape: J-45
Top: Sitka spruce
Back: Mahogany
Side: Mahogany
Bracing: Traditional hand scalloped X-bracing
Binding: Multi-ply top, single-ply back
Finish: Nitrocellulose

Neck

Material: Mahogany Profile: Slim Taper Scale Length: 24.75" / 628.65mm Fingerboard Material: Rosewood Fingerboard Radius: 12" Number Of Frets: 20 Frets: Standard Nut Material: Black Nut Width: 1.72" / 43.81mm Inlays: Mother-of-pearl Dots Joint: Compound Dovetail Neck-to-body

Hardware

Tuner Plating: Nickel Bridge: Traditional belly up Saddle Material: Tusq Tuning Machines: Grover Rotomatics w/ kidney buttons Pickguard: Tear drop Truss Rod Cover: B/W Bridge Pins: Tusq

Electronics

Under Saddle Pickup: LR Baggs VTC Controls: Volume and Tone controls