How To Downgrade Ps3 Firmware 4.89 To 4.88 Better -

That is a scam. No USB stick alone can bypass Sony’s RSA signature checks on 4.89.

Warning: Requires advanced soldering skills or an E3 Flasher kit. how to downgrade ps3 firmware 4.89 to 4.88

The most famous method bypasses Sony entirely using a hardware flasher (like the E3 Flasher or a Teensy 2.0++). This device physically clips onto the NOR flash chip on the PS3’s motherboard. That is a scam