Graph Tech Black Tusq XL Martin Slotted Nut
The PT-M600-00 is a great option to replace or upgrade the nut on your six string Martin style acoustic guitar and other guitars that require angled nuts.
It was specifically designed for Martin and has an angled bottom and is pre-slotted for a quick and simple install.
The PT-M600-00 is also available in a convenient 10 pack (LT-M600-10).