RM-U421 remote control can also be used to control other Sony devices, such as audio receivers and amplifiers. However, the specific compatibility of the remote control with other devices may vary. To check if the RM-U421 remote control is compatible with a specific Sony device
Sony STR-DE Series Receivers: Natively paired with or acts as a direct technical fit for the Sony STR-DE525, STR-DE625, and related home theater receiver tiers matching this late-1990s multi-channel architecture.
