Min version	XP	2003/XP64 SP1	Vista	7	8 Pre RTM	8
Max version	2003/XP64	2003/XP64 SP2	Vista SP2	7 SP1		10 TH2
x86 offset offset:bitpos	Field Name
0x0000	long Count		volatile long Count			long Count
0x0004	struct _KTHREAD * Owner				void * Owner
0x0008	unsigned long Contention
0x000C	struct _KEVENT Event	struct _KEVENT Gate		struct _KEVENT Event
0x001C	unsigned long OldIrql