RAM & Memory Upgrades
256MB (2 x 128MB) PC133 133MHz 168-PIN SDRAM DIMM MEMORY RAM KIT COMPATIBLE WITH IMAC G3, EMAC G4, POWERMAC G4
SIZE/CAPACITY: 256MB KIT (2 x 128MB) VOLTAGE/POWER CONSUMPTION: 3.3v CAS LATENCY: CL3 SPEED: PC133 (133MHz) TYPE/INTERFACE: 168-PIN SDRAM DIMM 168-PIN IMAC G3/EMAC G4/POWERMAC G3&G4 SDRAM DIMM
https://www.bizrate.co.uk/ram_memoryupgrades/256mb-2-x-128mb-pc133-oid40350142524.html