This listing is for 4 matching‑lot STMicroelectronics M27C256B‑10F1 UV‑EPROMs, all sharing date code 9G004 V5. These are premium ceramic DIP‑28 windowed EPROMs, ideal for arcade boards, synthesizers, industrial controllers, and restoration work requiring consistent, same‑lot devices.

Features: • 256 Kbit (32K × 8) UV‑erasable EPROM • 100 ns access time (‑10 speed grade) • Ceramic DIP‑28 package with quartz UV window • Matching‑lot batch — all 4 pcs date code 9G004 V5 • Clean, tested, and verified blank • Pins show signs of prior insertion/handling • Shipped pressed into anti‑static foam inside a rigid 6×8 photo mailer

These are high‑quality, tested ceramic EPROMs — perfect for applications where consistency and reliability matter. Catalog ID A0140