diff --git a/nx/include/switch/services/ns.h b/nx/include/switch/services/ns.h
index c3826f35..baee0558 100644
--- a/nx/include/switch/services/ns.h
+++ b/nx/include/switch/services/ns.h
@@ -165,7 +165,7 @@ Result nsvmInitialize(void);
 void nsvmExit(void);
 
 Result nsvmNeedsUpdateVulnerability(bool *out);
-Result nsvmGetSafeSystemVersion(u16 *out);
+Result nsvmGetSafeSystemVersion(NcmContentMetaKey *out); ///< [4.0.0+]
 
 ///@}
 
diff --git a/nx/source/services/ns.c b/nx/source/services/ns.c
index 98fbdf59..a05fc855 100644
--- a/nx/source/services/ns.c
+++ b/nx/source/services/ns.c
@@ -233,8 +233,8 @@ Result nsvmNeedsUpdateVulnerability(bool *out) {
     return _nsCmdNoInOutBool(srv, out, 1200);
 }
 
-Result nsvmGetSafeSystemVersion(u16 *out) {
-    if (hosversionBefore(3,0,0))
+Result nsvmGetSafeSystemVersion(NcmContentMetaKey *out) {
+    if (hosversionBefore(4,0,0))
         return MAKERESULT(Module_Libnx, LibnxError_IncompatSysVer);
 
     return serviceDispatchOut(&g_nsvmSrv, 1202, out);