diff --git a/src/temperatur.h b/src/temperatur.h
index 6063d96..010365b 100644
--- a/src/temperatur.h
+++ b/src/temperatur.h
@@ -11,4 +11,5 @@ float KzuC(float tempK);
 float KzuF(float tempK);
 
 const char* getFirstUnit(int input);
+const char* getSecondUnit(int input);
 #endif //TEMPERATUR_H
diff --git a/test/test_temperatur.c b/test/test_temperatur.c
index c1a14fb..04485a8 100644
--- a/test/test_temperatur.c
+++ b/test/test_temperatur.c
@@ -59,4 +59,10 @@ const char *result = getFirstUnit(1);
 char expected[] = "Celsius";
 TEST_ASSERT_EQUAL_STRING(expected, result);
 }
+void test_returnUnit_second(void)
+{
+const char *result = getSecondUnit(2);
+char expected[] = " Kelvin";
+TEST_ASSERT_EQUAL_STRING(expected, result);
+}
 #endif