diff --git a/app/src/main/java/net/thauvin/erik/android/tesremoteprogrammer/util/Strings.kt b/app/src/main/java/net/thauvin/erik/android/tesremoteprogrammer/util/Strings.kt
index cd0d38a..28f724e 100644
--- a/app/src/main/java/net/thauvin/erik/android/tesremoteprogrammer/util/Strings.kt
+++ b/app/src/main/java/net/thauvin/erik/android/tesremoteprogrammer/util/Strings.kt
@@ -17,7 +17,7 @@
  */
 package net.thauvin.erik.android.tesremoteprogrammer.util
 
-fun String.isDigits() : Boolean {
+fun String.isDigits(): Boolean {
     if (isBlank()) {
         return false
     }
@@ -31,6 +31,10 @@ fun String.isDigits() : Boolean {
     return true
 }
 
+fun String.isDKS(): Boolean {
+    return this.equals(Dtmf.DKS, true)
+}
+
 fun String.replaceAll(replace: Array<Pair<String, String>>): String {
     val result = StringBuilder(this)
     var offset: Int