diff --git a/usr.bin/procstat/procstat.1 b/usr.bin/procstat/procstat.1
--- a/usr.bin/procstat/procstat.1
+++ b/usr.bin/procstat/procstat.1
@@ -479,13 +479,11 @@
 .Pp
 .Bl -tag -width indent -compact
 .It UDD
-.Dv IPPROTO_UDP ;
-see
-.Xr udp 4 .
+Datagram socket.
 .It UDS
-.Dv IPPROTO_TCP ;
-see
-.Xr tcp 4 .
+Stream socket.
+.It UDQ
+Sequential Packet Stream socket.
 .It UD?
 unknown protocol.
 .El
diff --git a/usr.bin/procstat/procstat_files.c b/usr.bin/procstat/procstat_files.c
--- a/usr.bin/procstat/procstat_files.c
+++ b/usr.bin/procstat/procstat_files.c
@@ -75,6 +75,8 @@
 			return ("UDS");
 		case SOCK_DGRAM:
 			return ("UDD");
+		case SOCK_SEQPACKET:
+			return ("UDQ");
 		default:
 			return ("UD?");
 		}