NtCreateTimer2 - NtDoc

#ifndef _NTEXAPI_H
#if (PHNT_MODE != PHNT_MODE_KERNEL)
#if (PHNT_VERSION >= PHNT_THRESHOLD)

NTSYSCALLAPI
NTSTATUS
NTAPI
NtCreateTimer2(
    _Out_ PHANDLE TimerHandle,
    _In_opt_ PVOID Reserved1,
    _In_opt_ PCOBJECT_ATTRIBUTES ObjectAttributes,
    _In_ ULONG Attributes, // TIMER_TYPE
    _In_ ACCESS_MASK DesiredAccess
    );

#endif
#endif
#endif
View code on GitHub

#ifndef _NTZWAPI_H

NTSYSCALLAPI
NTSTATUS
NTAPI
ZwCreateTimer2(
    _Out_ PHANDLE TimerHandle,
    _In_opt_ PVOID Reserved1,
    _In_opt_ PCOBJECT_ATTRIBUTES ObjectAttributes,
    _In_ ULONG Attributes, // TIMER_TYPE
    _In_ ACCESS_MASK DesiredAccess
    );

#endif
View code on GitHub