diff --git a/lib/libmt/mtlib.c b/lib/libmt/mtlib.c
index ad73381c5822..f6acba21f4ef 100644
--- a/lib/libmt/mtlib.c
+++ b/lib/libmt/mtlib.c
@@ -568,6 +568,15 @@ static struct densities {
 	 *
 	 * IBM 3592 definitions obtained from second edition of the IBM
 	 * System Storage Tape Drive 3592 SCSI Reference (May 25, 2012).
+	 *
+	 * DAT-72 and DAT-160 bpi values taken from "HP StorageWorks DAT160
+	 * tape drive white paper", dated June 2007.
+	 *
+	 * DAT-160 / SDLT220 density code (0x48) conflict information
+	 * found here:
+	 *
+	 * http://h20564.www2.hp.com/hpsc/doc/public/display?docId=emr_na-c01065117&sp4ts.oid=429311
+ 	 * (Document ID c01065117)
 	 */
 	/*Num.  bpmm    bpi     Reference     */
 	{ 0x1,	32,	800,	"X3.22-1983" },
@@ -613,6 +622,14 @@ static struct densities {
 	{ 0x42, 7398,   187909, "LTO-2" },
 	{ 0x44, 9638,   244805, "LTO-3" }, 
 	{ 0x46, 12725,  323215, "LTO-4" }, 
+	{ 0x47, 6417,   163000, "DAT-72" },
+	/*
+	 * XXX KDM note that 0x48 is also the density code for DAT-160.
+	 * For some reason they used overlapping density codes.
+	 */
+#if 0
+	{ 0x48, 6870,   174500, "DAT-160" },
+#endif
 	{ 0x48, 5236,   133000, "SDLTapeI(110)" },
 	{ 0x49, 7598,   193000, "SDLTapeI(160)" },
 	{ 0x4a,     0,       0, "T10000A" },
diff --git a/usr.bin/mt/mt.1 b/usr.bin/mt/mt.1
index 849774c5d74f..33c1c1814725 100644
--- a/usr.bin/mt/mt.1
+++ b/usr.bin/mt/mt.1
@@ -29,7 +29,7 @@
 .\"	@(#)mt.1	8.1 (Berkeley) 6/6/93
 .\" $FreeBSD$
 .\"
-.Dd February 12, 2014
+.Dd March 3, 2014
 .Dt MT 1
 .Os
 .Sh NAME
@@ -503,7 +503,8 @@ Value  Width        Tracks    Density         Code Type Reference   Note
 0x42   12.7  (0.5)  512      7,398  (187,909)       C   LTO-2
 0x44   12.7  (0.5)  704      9,638  (244,805)       C   LTO-3
 0x46   12.7  (0.5)  896      12,725 (323,215)       C   LTO-4
-0x48   12.7  (0.5)  448      5,236  (133,000) PRML  C   SDLTapeI(110) 6,8
+0x47    3.81 (0.25)   ?      6,417  (163,000)       CS  DAT-72
+0x48   12.7  (0.5)  448      5,236  (133,000) PRML  C   SDLTapeI(110) 6,8,13
 0x49   12.7  (0.5)  448      7,598  (193,000) PRML  C   SDLTapeI(160) 6,8
 0x4A   12.7  (0.5)  768          ?                  C   T10000A      10
 0x4B   12.7  (0.5) 1152          ?                  C   T10000B      10
@@ -556,6 +557,7 @@ NOTES
     density code is 0x90.
 12. This is Exabyte 8500 uncompressed format.  The compressed format
     density code is 0x8c.
+13. This density code (0x48) was also used for DAT-160.
 .Ed
 .Sh ENVIRONMENT
 .Bl -tag -width ".Ev TAPE"