diff --git a/src/features/calt.fea b/src/features/calt.fea
index 93fef6c64..5c1200c5d 100644
--- a/src/features/calt.fea
+++ b/src/features/calt.fea
@@ -351,18 +351,36 @@ sub @Numeral @Whitespace @Whitespace @between_num_L' @Whitespace @Whitespace @Nu
 # END case
 # -------------------------------------------------------------------------------------
 # BEGIN NxN
+# x surrounded by numbers, e.g:
+#   3x4   -> 3×4
+#   10x20 -> 10×20
+#   0x10  -> 0x10   No substitution
+#
+@NumNoZero = [
+  #
+  # NOTE! Keep this up to date with @Whitespace
+  #
+  #   1. in glyphs, copy list from font into > features > Whitespace class
+  #   2. paste & replace this list here
+  #   3. remove all "zero" glyphs
+  #
+  one two twostroke three four five Tonefive six seven eight nine
+  one.ss01 three.1 four.ss01 six.ss01 nine.ss01
+  one.tf two.tf three.tf four.tf five.tf six.tf seven.tf eight.tf
+  nine.tf one.tf.ss01 three.1.tf four.tf.ss01 six.tf.ss01
+  nine.tf.ss01
+];
 
-# x surrounded by numbers, e.g. 3x4 -> 3×4
-sub @Numeral x' @Numeral                                                 by multiply.case; # 3x9
-sub @Numeral @Whitespace x' @Numeral                                     by multiply.case; # 3 x9
-sub @Numeral @Whitespace @Whitespace x' @Numeral                         by multiply.case; # 3  x9
-sub @Numeral x' @Whitespace @Numeral                                     by multiply.case; # 3x 9
-sub @Numeral @Whitespace x' @Whitespace @Numeral                         by multiply.case; # 3 x 9
-sub @Numeral @Whitespace @Whitespace x' @Whitespace @Numeral             by multiply.case; # 3  x 9
-sub @Numeral x' @Whitespace @Whitespace @Numeral                         by multiply.case; # 3x  9
-sub @Numeral @Whitespace x' @Whitespace @Whitespace @Numeral             by multiply.case; # 3 x  9
-sub @Numeral @Whitespace @Whitespace x' @Whitespace @Whitespace @Numeral by multiply.case; # 3  x  9
+sub @NumNoZero x' @Numeral by multiply.case; # "3x9" "1x0"
+sub @Numeral @Numeral x' @Numeral by multiply.case; # "10x0"
+
+sub @NumNoZero @Whitespace x' @Numeral by multiply.case; # "3 x9" "1 x0"
+sub @NumNoZero @Whitespace x' @Whitespace @Numeral by multiply.case; # "3 x 9" "1 x 0"
+sub @NumNoZero x' @Whitespace @Numeral by multiply.case; # "3x 9" "1x 0"
+
+sub @Numeral @Numeral @Whitespace x' @Numeral by multiply.case; # "10 x0"
+sub @Numeral @Numeral @Whitespace x' @Whitespace @Numeral by multiply.case; # "10 x 0"
+sub @Numeral @Numeral x' @Whitespace @Numeral by multiply.case; # "10x 0"
 
 # END NxN
 # -------------------------------------------------------------------------------------
-