diff --git a/src/GsmDetector.php b/src/GsmDetector.php
index 060ce2b..08f4657 100644
--- a/src/GsmDetector.php
+++ b/src/GsmDetector.php
@@ -15,9 +15,9 @@ class GsmDetector
 
     private static $mobileKeyName = "mobile";
 
-    private static $mobilePrefixLength = 2;
+    private static $mobilePrefixDigits = 2;
 
-    private static $fixPrefixLength = 3;
+    private static $fixPrefixDigits = 3;
 
     /**
      * GsmDetector constructor.
@@ -164,14 +164,14 @@ public static function setConfig(array $config)
         self::$config = $config;
     }
 
-    public static function setMobilePrefixLength(int $length)
+    public static function setMobilePrefixDigits(int $length)
     {
-        self::$mobilePrefixLength = $length;
+        self::$mobilePrefixDigits = $length;
     }
 
-    public static function setFixPrefixLength(int $length)
+    public static function setFixPrefixDigits(int $length)
     {
-        self::$fixPrefixLength = $length;
+        self::$fixPrefixDigits = $length;
     }
 
     /**
@@ -220,7 +220,7 @@ private function getNumberPrefix($value, $prefixLength)
 
     private function hasValue($prefix, $value)
     {
-        return in_array($this->getNumberPrefix($value, self::$mobilePrefixLength), $prefix) ||
-            in_array($this->getNumberPrefix($value, self::$fixPrefixLength), $prefix);
+        return in_array($this->getNumberPrefix($value, self::$mobilePrefixDigits), $prefix) ||
+            in_array($this->getNumberPrefix($value, self::$fixPrefixDigits), $prefix);
     }
 }
diff --git a/tests/GsmDetectorTest.php b/tests/GsmDetectorTest.php
index 25e80c8..15da59e 100644
--- a/tests/GsmDetectorTest.php
+++ b/tests/GsmDetectorTest.php
@@ -29,7 +29,7 @@ public function test_is_gsm()
         $this->assertFalse($gsmDetector->isGsm('togocel', '26000000'));
         $this->assertFalse($gsmDetector->isGsm('orange', '29000000'));
 
-        GsmDetector::setFixPrefixLength(3);
+        GsmDetector::setFixPrefixDigits(3);
 
         $this->assertFalse($gsmDetector->isGsm('orange', '215000000'));
     }
@@ -54,7 +54,7 @@ public function test_is_gsm_with_type()
         $this->assertFalse($gsmDetector->isGsmWithType('togocel', 'fix', '01000000'));
         $this->assertTrue($gsmDetector->isGsmWithType('orange','fix', '35000000'));
 
-        GsmDetector::setFixPrefixLength(3);
+        GsmDetector::setFixPrefixDigits(3);
 
         $this->assertTrue($gsmDetector->isGsmWithType('orange','fix', '21500000'));
     }
@@ -81,7 +81,7 @@ public function test_is_gsm_name()
         $this->assertTrue($gsmDetector->isOrange('09000000'));
         $this->assertTrue($gsmDetector->isOrange('22000000'));
 
-        GsmDetector::setFixPrefixLength(3);
+        GsmDetector::setFixPrefixDigits(3);
 
         $this->assertTrue($gsmDetector->isOrange('21500000'));
     }