This listing is for a very rare new-old-stock Signetics 82S09 Static RAM (576 bits, 64 x 9). 

The 82S09 is an unusual early memory chip. It held 576 bits. Most memory devices had multiples of 2 in capacity. The 82S09 is designed to store bytes of data with a parity bit, so 9-bits total. Without the parity bit, the device stores 64 bytes, or 512, bits of data. The 82S09 has 9 input lines and 9 output lines.

The chip offered here is a never used new-old-stock Signetics 82S09 SRAM. The chip was made in the 7th week of 1974, over 40 years ago. The 28 leads are gold and the body is white ceramic with a gold ceramic lid. The chip is in excellent condition. It also comes in its original packaging. This chip would  be a great addition to your memory collection.