diff --git a/converters/fromZigbee.js b/converters/fromZigbee.js
index 2e824f55587d9..adf9a2cf5b6f1 100644
--- a/converters/fromZigbee.js
+++ b/converters/fromZigbee.js
@@ -1,3 +1,5 @@
+'use strict';
+
 const debounce = require('debounce');
 
 const clickLookup = {
diff --git a/converters/toZigbee.js b/converters/toZigbee.js
index 0f15b7ad7df39..a3cb7d7a8e41c 100644
--- a/converters/toZigbee.js
+++ b/converters/toZigbee.js
@@ -1,3 +1,5 @@
+'use strict';
+
 const converters = {
     onoff: {
         key: 'state',
diff --git a/devices.js b/devices.js
index 42821f7bcf5e6..7d02d9ef1d1e3 100644
--- a/devices.js
+++ b/devices.js
@@ -1,3 +1,5 @@
+'use strict';
+
 const fz = require('./converters/fromZigbee');
 const tz = require('./converters/toZigbee');
 
diff --git a/index.js b/index.js
index 8debe719e912e..e9da87d4fb454 100644
--- a/index.js
+++ b/index.js
@@ -1,3 +1,5 @@
+'use strict';
+
 const devices = require('./devices');
 
 module.exports = {
diff --git a/test/verify.js b/test/verify.js
index de6716e328330..2509f6994406f 100644
--- a/test/verify.js
+++ b/test/verify.js
@@ -1,3 +1,5 @@
+'use strict';
+
 const devices = require('../devices');
 const assert = require('assert');