This is a CAN-type OPA637AM operational amplifier from Burr-Brown (BB), now Texas Instruments (TI), known as a high-precision op-amp. The OPA637 is considered a faster version of the OPA627 without phase compensation (C?), resulting in a faster settling time of 550ns → 450ns (according to the catalog). However, due to the above reason, it performs best when used with a gain of 5x or more. The catalog states that the OPA627 is better for unity gain applications, while the OPA637 is better for a gain of 5. It is said to have a calm and composed atmosphere overall, suitable for audio applications. *Note: Use with a gain of 5x or more.* You may find more information about the product on the Digikey website. *About 20 years ago, when I was working for a manufacturer, I enjoyed DIY audio hobbies such as phono equalizers and DACs, and I purchased these through a trading company.* [Quantity]: 2 x OPA637AM [Condition]: Unused [Included]: None (with delivery socket) [Application]: Modification or DIY of audio equipment, etc. ★To prevent product substitution, returns are not accepted. Please purchase only if you agree to the above.