diff --git a/src/boards/239.c b/src/boards/239.c
new file mode 100644
index 0000000..72e1192
--- /dev/null
+++ b/src/boards/239.c
@@ -0,0 +1,38 @@
+/* FCE Ultra - NES/Famicom Emulator
+ *
+ * Copyright notice for this file:
+ *  Copyright (C) 2025 NewRisingSun
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include "mapinc.h"
+#include "asic_latch.h"
+
+static void sync () {
+	if (Latch_address &0x04)
+		setprg32(0x8000, Latch_address >>1);
+	else {
+		setprg16(0x8000, Latch_address);
+		setprg16(0xC000, Latch_address);
+	}
+	setchr8(Latch_address);
+	setmirror(Latch_address &0x10? MI_H: MI_V);
+}
+
+void Mapper239_Init (CartInfo *info) {
+	Latch_init(info, sync, 0x8000, 0xFFFF, NULL);
+	info->Reset = Latch_clear;
+}
diff --git a/src/ines.c b/src/ines.c
index 4c4868c..2774856 100644
--- a/src/ines.c
+++ b/src/ines.c
@@ -692,7 +692,7 @@ INES_BOARD_BEGIN()
 	INES_BOARD( "Realtec 8031/8155/8099/8106", 236, Mapper236_Init         )
 	INES_BOARD( "Teletubbies / Y2K",        237, Mapper237_Init         )
 	INES_BOARD( "UNL6035052",               238, UNL6035052_Init        )
-/*    INES_BOARD( "",                            239, Mapper239_Init ) */
+	INES_BOARD( "OK-043",                   239, Mapper239_Init         )
 	INES_BOARD( "",                         240, Mapper240_Init         )
 	INES_BOARD( "",                         241, Mapper241_Init         )
 	INES_BOARD( "43272",                    242, Mapper242_Init         )
diff --git a/src/ines.h b/src/ines.h
index f342e56..9c5f9ba 100644
--- a/src/ines.h
+++ b/src/ines.h
@@ -236,6 +236,7 @@ void Mapper234_Init(CartInfo *);
 void Mapper235_Init(CartInfo *);
 void Mapper236_Init(CartInfo *);
 void Mapper237_Init(CartInfo *);
+void Mapper239_Init(CartInfo *);
 void Mapper240_Init(CartInfo *);
 void Mapper241_Init(CartInfo *);
 void Mapper242_Init(CartInfo *);