HP 4GB 260-Pin DDR4 SO-DIMM Unbuffered DDR4 2133 (PC4 17000) System Specific Memory Model T7B76UT Voltage: 1.2V Compatible System: Compatible With: HP EliteBook 820 G3 HP EliteBook 840 G3 HP EliteBook 850 G3 HP ProBook 430 G3 HP ProBook 440 G3 HP ProBook 450 G3 HP ProBook 455 G3 HP ProBook 470 G3 HP ProBook 640 G2 HP ProBook 650 G2 HP ZBook 15 G3 Mobile Workstation HP ZBook 15u G3 Mobile Workstation HP ZBook 17 G3 Mobile Workstation HP ZBook Studio G3 Mobile Workstation