Former Binance CEO Changpeng Zhao (CZ) has reaffirmed his stance on hardware wallet security, stating that private keys must never leave the device under any circumstances. His comments were initially reported in the context of a review of a new hardware wallet product intended for release next year. The statement emphasizes strict isolation as a mandatory requirement for self-custody solutions. CZ argues that for a device to be secure, the private key architecture must ensure it remains permanently isolated within the hardware environment to prevent extraction risks. [Update 1] Reports indicate that this commentary coincides with YZi Labs (formerly Binance Labs) announcing an investment in OneKey, an open-source hardware wallet provider. The specific mention of OneKey clarifies the context of the security discussion, highlighting the investment firm's focus on backing infrastructure that meets these strict self-custody standards.