diff --git a/tun/tun_netbsd.go b/tun/tun_netbsd.go
index e5834c1..9c8a0fe 100644
--- a/tun/tun_netbsd.go
+++ b/tun/tun_netbsd.go
@@ -164,7 +164,7 @@ func CreateTUN(name string, mtu int) (Device, error) {
         uintptr(unsafe.Pointer(&ifheadmode)),
     )
 
-    if errno != 0 || ifheadmode != 1 {
+    if errno != 0 || ifheadmode == 0 {
         tunfile.Close()
         return nil, fmt.Errorf("Unable to validate IFHEAD mode: %v (ifheadmode = %d)", errno, ifheadmode)
     }