diff --git a/kernel/2dx_image/scripts-custom/2dx_evaluateLattice.script b/kernel/2dx_image/scripts-custom/2dx_evaluateLattice.script
index 76b41a18..fdcc6b81 100755
--- a/kernel/2dx_image/scripts-custom/2dx_evaluateLattice.script
+++ b/kernel/2dx_image/scripts-custom/2dx_evaluateLattice.script
@@ -136,6 +136,7 @@ set peakNum = "140"
 # DISPLAY: tempkeep
 # DISPLAY: comment
 # DISPLAY: defocus
+# DISPLAY: flag_lefthanded_lattice
 #
 #$end_local_vars
 #
@@ -163,6 +164,7 @@ set SYM = ""
 set det_tilt = ""
 set tempkeep = ""
 set defocus = ""
+set flag_lefthanded_lattice = ""
 #
 #$end_vars
 #
@@ -753,6 +755,11 @@ echo "set LATTICE_TLTANG  = "\"${LATTICE_TLTANG}\"  >> LOGS/${scriptname}.result
 echo "set LATTICE_TLTAXA  = "\"${LATTICE_TLTAXA}\"  >> LOGS/${scriptname}.results
 echo "set LATTICE_TAXA    = "\"${LATTICE_TAXA}\"    >> LOGS/${scriptname}.results
 echo "set LATTICE_TANGL   = "\"${LATTICE_TANGL}\"   >> LOGS/${scriptname}.results
+if ( ${hand} == "1" ) then
+  echo "set flag_lefthanded_lattice = "\"n\"        >> LOGS/${scriptname}.results
+else
+  echo "set flag_lefthanded_lattice = "\"y\"        >> LOGS/${scriptname}.results
+endif
 #
 echo "# IMAGE-IMPORTANT: FFTIR/${nonmaskimagename}_fft.mrc <FFT of Nonmasked Image>" >> LOGS/${scriptname}.results
 echo "# IMAGE-IMPORTANT: FFTIR/${nonmaskimagename}_red_fft.mrc <FFT of Downsampled Nonmasked Image>" >> LOGS/${scriptname}.results
diff --git a/kernel/config/2dx_master.cfg b/kernel/config/2dx_master.cfg
index 56cc52f7..b719cd9a 100755
--- a/kernel/config/2dx_master.cfg
+++ b/kernel/config/2dx_master.cfg
@@ -1715,6 +1715,16 @@ set backuplattice = "0.0,0.0,0.0,0.0"
 # SYNC_WITH_UPPER_LEVEL: NO
 set plotres_rings = "36,24,18,12,7"
 #
+# LABEL: FLAG: The Lattice is Lefthanded
+# LEGEND: Only a flag, do not edit this.
+# EXAMPLE: flag_lefthanded_lattice = "n"
+# HELP: http://2dx.org/documentation/2dx-software/parameters/flag
+# TYPE: Bool "y;n"
+# INHERITABLE_UPON_INIT: NO
+# SYNC_WITH_UPPER_LEVEL: NO
+# USERLEVEL: SIMPLE
+set flag_lefthanded_lattice = "n"
+#
 #=============================================================================
 # SECTION: SpotList Determination
 #=============================================================================
diff --git a/kernel/config/2dx_merge/projectMenu.inf b/kernel/config/2dx_merge/projectMenu.inf
index 27d02d26..6b9c3aa4 100755
--- a/kernel/config/2dx_merge/projectMenu.inf
+++ b/kernel/config/2dx_merge/projectMenu.inf
@@ -55,6 +55,7 @@ beamtilt_change (BeamTilt Change,mouseover="Last Beam Tilt Change",nonlockable,s
 realcell (RealCell,mouseover="Global Real Cell Vectors",nonlockable,sortable,"%.1f,%.1f")
 realang (RealAngle,mouseover="Global Real Cell Angle",nonlockable,sortable,"%.1f")
 lattice (Lattice,mouseover="Reciprocal Lattice",nonlockable,sortable)
+flag_lefthanded_lattice (LeftHand,mouseover="Lattice is lefthanded",nonlockable,sortable,checkbox)
 ML_use_for_merging (UseML,mouseover="Use Single Particle result",nonlockable,sortable,checkbox)
 ctfrev (rCTF,mouseover="Revert contrast",nonlockable,sortable,checkbox)
 rot90 (R90,mouseover="Rot90",nonlockable,sortable,checkbox)
diff --git a/kernel/mrc/source/2dx_lencalc.for b/kernel/mrc/source/2dx_lencalc.for
index b4b48fa7..870fd90e 100755
--- a/kernel/mrc/source/2dx_lencalc.for
+++ b/kernel/mrc/source/2dx_lencalc.for
@@ -67,6 +67,7 @@ C
         ihand = -1 
         WRITE(11,'('':: ##### ATTENTION: Left-handed lattice ####### '',/,I4)')ihand
       endif
+
 C
 C-----transform tilted reciprocal lattice into a tilted real-space lattice
 C