diff --git a/ld/libfiles.ntsc-beta.inc b/ld/libfiles.ntsc-beta.inc
index 05f78a789..f7407994d 100644
--- a/ld/libfiles.ntsc-beta.inc
+++ b/ld/libfiles.ntsc-beta.inc
@@ -186,6 +186,7 @@
 	build/ROMID/lib/ultra/io/contreaddata.o (section); \
 	build/ROMID/lib/ultra/io/motor.o (section); \
 	build/ROMID/lib/lib_4f9b0.o (section); \
+	build/ROMID/lib/ultra/gu/coss.o (section); \
 	build/ROMID/lib/ultra/gu/sins.o (section); \
 	build/ROMID/lib/ultra/gu/ortho.o (section); \
 	build/ROMID/lib/ultra/gu/frustum.o (section); \
diff --git a/ld/libfiles.ntsc-final.inc b/ld/libfiles.ntsc-final.inc
index 9a387d697..216978f23 100644
--- a/ld/libfiles.ntsc-final.inc
+++ b/ld/libfiles.ntsc-final.inc
@@ -182,6 +182,7 @@
 	build/ROMID/lib/ultra/io/contreaddata.o (section); \
 	build/ROMID/lib/ultra/io/motor.o (section); \
 	build/ROMID/lib/lib_4f9b0.o (section); \
+	build/ROMID/lib/ultra/gu/coss.o (section); \
 	build/ROMID/lib/ultra/gu/sins.o (section); \
 	build/ROMID/lib/ultra/gu/ortho.o (section); \
 	build/ROMID/lib/ultra/gu/frustum.o (section); \
diff --git a/ld/libfiles.pal-final.inc b/ld/libfiles.pal-final.inc
index 22be35872..6790ce371 100644
--- a/ld/libfiles.pal-final.inc
+++ b/ld/libfiles.pal-final.inc
@@ -182,6 +182,7 @@
 	build/ROMID/lib/ultra/io/contreaddata.o (section); \
 	build/ROMID/lib/ultra/io/motor.o (section); \
 	build/ROMID/lib/lib_4f9b0.o (section); \
+	build/ROMID/lib/ultra/gu/coss.o (section); \
 	build/ROMID/lib/ultra/gu/sins.o (section); \
 	build/ROMID/lib/ultra/gu/ortho.o (section); \
 	build/ROMID/lib/ultra/gu/frustum.o (section); \
diff --git a/src/include/PR/gu.h b/src/include/PR/gu.h
index e98df6567..322d2b323 100644
--- a/src/include/PR/gu.h
+++ b/src/include/PR/gu.h
@@ -28,6 +28,7 @@ void guLookAt(Mtx *m, float xEye, float yEye, float zEye,
 		float xAt,  float yAt,  float zAt,
 		float xUp,  float yUp,  float zUp);
 
+signed short coss(unsigned short x);
 signed short sins(unsigned short x);
 
 /* Used only in Fast3DEX2 */
diff --git a/src/include/lib/lib_4f9b0.h b/src/include/lib/lib_4f9b0.h
index d3bbd3c4b..2190484b3 100644
--- a/src/include/lib/lib_4f9b0.h
+++ b/src/include/lib/lib_4f9b0.h
@@ -5,6 +5,5 @@
 #include "types.h"
 
 u32 func0004f9b0(void);
-u32 func0004fbc0(void);
 
 #endif
diff --git a/src/lib/lib_4f9b0.c b/src/lib/lib_4f9b0.c
index 30c36da14..154f9b445 100644
--- a/src/lib/lib_4f9b0.c
+++ b/src/lib/lib_4f9b0.c
@@ -149,19 +149,3 @@ glabel func0004fb70
 /*    4fbb8:	03e00008 */ 	jr	$ra
 /*    4fbbc:	00000000 */ 	nop
 );
-
-GLOBAL_ASM(
-glabel func0004fbc0
-/*    4fbc0:	27bdffe8 */ 	addiu	$sp,$sp,-24
-/*    4fbc4:	afa40018 */ 	sw	$a0,0x18($sp)
-/*    4fbc8:	00802825 */ 	or	$a1,$a0,$zero
-/*    4fbcc:	24a44000 */ 	addiu	$a0,$a1,0x4000
-/*    4fbd0:	afbf0014 */ 	sw	$ra,0x14($sp)
-/*    4fbd4:	308effff */ 	andi	$t6,$a0,0xffff
-/*    4fbd8:	0c013efc */ 	jal	sins
-/*    4fbdc:	01c02025 */ 	or	$a0,$t6,$zero
-/*    4fbe0:	8fbf0014 */ 	lw	$ra,0x14($sp)
-/*    4fbe4:	27bd0018 */ 	addiu	$sp,$sp,0x18
-/*    4fbe8:	03e00008 */ 	jr	$ra
-/*    4fbec:	00000000 */ 	nop
-);
diff --git a/src/lib/model.c b/src/lib/model.c
index b16aa30d7..0b33d64fa 100644
--- a/src/lib/model.c
+++ b/src/lib/model.c
@@ -8561,7 +8561,7 @@ glabel func0002124c
 /*    213b0:	00000000 */ 	nop
 /*    213b4:	00025280 */ 	sll	$t2,$v0,0xa
 /*    213b8:	3151ffff */ 	andi	$s1,$t2,0xffff
-/*    213bc:	0c013ef0 */ 	jal	func0004fbc0
+/*    213bc:	0c013ef0 */ 	jal	coss
 /*    213c0:	3144ffff */ 	andi	$a0,$t2,0xffff
 /*    213c4:	00025940 */ 	sll	$t3,$v0,0x5
 /*    213c8:	01770019 */ 	multu	$t3,$s7
@@ -9200,7 +9200,7 @@ glabel var70054454
 /*    21d58:	00608825 */ 	or	$s1,$v1,$zero
 /*    21d5c:	00026a80 */ 	sll	$t5,$v0,0xa
 /*    21d60:	a7ad0062 */ 	sh	$t5,0x62($sp)
-/*    21d64:	0c013ef0 */ 	jal	func0004fbc0
+/*    21d64:	0c013ef0 */ 	jal	coss
 /*    21d68:	31a4ffff */ 	andi	$a0,$t5,0xffff
 /*    21d6c:	922e0004 */ 	lbu	$t6,0x4($s1)
 /*    21d70:	97a40062 */ 	lhu	$a0,0x62($sp)
diff --git a/src/lib/ultra/gu/coss.c b/src/lib/ultra/gu/coss.c
new file mode 100644
index 000000000..d0f161019
--- /dev/null
+++ b/src/lib/ultra/gu/coss.c
@@ -0,0 +1,11 @@
+#include <ultra64.h>
+#include "constants.h"
+#include "bss.h"
+#include "lib/lib_16110.h"
+#include "data.h"
+#include "types.h"
+
+signed short coss(unsigned short x)
+{
+	return sins ((unsigned short) (x + 0x4000));
+}