The FAT-20 is a type of tremolo bridge equipped on some Ibanez models. It is produced exclusively for Ibanez and was introduced in 2002.
The FAT-20 is the top Ibanez synchronized trem used in RG-style guitars, above the FAT-6 and FAT-10. It's available in chrome (part number 2FA1C20C) or black (2FA1C20B) finishes for right-handed guitars and in chrome only (2FA1C20LC) for lefty guitars.
The FAT-20 tremolo was discontinued after 2012.