diff --git a/client/src/cmdlfindala.c b/client/src/cmdlfindala.c
index 7c19f1401..eec802bad 100644
--- a/client/src/cmdlfindala.c
+++ b/client/src/cmdlfindala.c
@@ -887,6 +887,16 @@ int getIndalaBits(uint8_t fc, uint16_t cn, uint8_t *bits) {
 }
 
 // Derived from getIndalaBits() by Matt Saunier 04 Jun 2021. Conforms to the Indala 4041X format, correctly calculates parity for 26-bit Wiegand.
+
+/*
+    Permutation table for this format, lower 4 bytes of card data.
+
+    0x40 |  1   | CN 6 | P Hi | CN 9 | CN A | CN 5 | P Lo | FC 1 |
+    0x50 | CN C | CN 0 | CN 5 | CN D | FC 5 | CN E | CN 7 | FC 4 |
+    0x60 | FC 3 | FC 6 | CN 1 | CN 8 | CN B | FC 2 | CN 4 |  1   |
+    0x70 | CN 3 | FC 7 | FC 0 | CN 2 |  0   |  0   |  0   |  0   |
+*/
+
 int getIndalaBits4041x(uint8_t fc, uint16_t cn, uint8_t *bits) {
 
     // Preamble and required values