diff --git a/src/features/features.h b/src/features/features.h
index 2ff2645..dfc1487 100644
--- a/src/features/features.h
+++ b/src/features/features.h
@@ -1,5 +1,6 @@
-#ifndef _FEATURES_H
-#define _FEATURES_H
+
+#ifndef FEATURES_H_
+#define FEATURES_H_
 
 #include "../include/sdk.h"
 
@@ -9,4 +10,4 @@ void bhop(usercmd_t* cmd);
 /* src/features/esp.c */
 void esp(void);
 
-#endif /* _FEATURES_H */
+#endif /* FEATURES_H_ */
diff --git a/src/include/cvars.h b/src/include/cvars.h
index 07a053c..7486c91 100644
--- a/src/include/cvars.h
+++ b/src/include/cvars.h
@@ -1,6 +1,6 @@
 
-#ifndef _CVARS_H
-#define _CVARS_H
+#ifndef CVARS_H_
+#define CVARS_H_
 
 #include "sdk.h"
 #include "globals.h"
@@ -36,4 +36,4 @@ DECL_CVAR_EXTERN(esp);
 
 bool cvars_init(void);
 
-#endif /* _CVARS_H */
+#endif /* CVARS_H_ */
diff --git a/src/include/globals.h b/src/include/globals.h
index 5ae6985..7119461 100644
--- a/src/include/globals.h
+++ b/src/include/globals.h
@@ -1,5 +1,6 @@
-#ifndef _GLOBALS_H
-#define _GLOBALS_H
+
+#ifndef GLOBALS_H_
+#define GLOBALS_H_
 
 #include "sdk.h"
 
@@ -37,4 +38,4 @@ bool globals_init(void);
 void globals_store(void);
 void globals_restore(void);
 
-#endif /* _GLOBALS_H */
+#endif /* GLOBALS_H_ */
diff --git a/src/include/hooks.h b/src/include/hooks.h
index 5e4aeb1..b176004 100644
--- a/src/include/hooks.h
+++ b/src/include/hooks.h
@@ -1,6 +1,6 @@
 
-#ifndef _HOOKS_H
-#define _HOOKS_H
+#ifndef HOOKS_H_
+#define HOOKS_H_
 
 /*----------------------------------------------------------------------------*/
 
@@ -63,4 +63,4 @@ bool hooks_init(void);
 DECL_HOOK_EXTERN(void, CL_CreateMove, float, usercmd_t*, int);
 DECL_HOOK_EXTERN(int, HUD_Redraw, float, int);
 
-#endif /* _HOOKS_H */
+#endif /* HOOKS_H_ */
diff --git a/src/include/main.h b/src/include/main.h
index 43fee82..57dcb67 100644
--- a/src/include/main.h
+++ b/src/include/main.h
@@ -1,8 +1,8 @@
 
-#ifndef _MAIN_H
-#define _MAIN_H
+#ifndef MAIN_H_
+#define MAIN_H_
 
 void load(void);
 void self_unload(void);
 
-#endif /* _MAIN_H */
+#endif /* MAIN_H_ */
diff --git a/src/include/sdk.h b/src/include/sdk.h
index 36492d5..7e773d0 100644
--- a/src/include/sdk.h
+++ b/src/include/sdk.h
@@ -1,5 +1,5 @@
-#ifndef _SDK_H
-#define _SDK_H
+#ifndef SDK_H_
+#define SDK_H_
 
 /*
  * cl_enginefunc_t:
@@ -22,17 +22,9 @@
 #include "sdk/common/triangleapi.h"
 
 /*
-#include "sdk/common/event_api.h"
-#include "sdk/common/mathlib.h"
-#include "sdk/common/r_studioint.h"
-#include "sdk/cl_dll/global_consts.h"
-#include "sdk/common/com_model.h"
-#include "sdk/engine/studio.h"
-#include "sdk/common/screenfade.h"
-#include "sdk/common/net_api.h"
-#include "sdk/common/parsemsg.h"
-*/
-
+ * Credits:
+ *   https://github.com/UnkwUsr/hlhax/blob/26491984996c8389efec977ed940c5a67a0ecca4/src/sdk.h#L45
+ */
 typedef struct cl_clientfuncs_s {
     int (*Initialize)(cl_enginefunc_t* pEnginefuncs, int iVersion);
     void (*HUD_Init)(void);
@@ -109,4 +101,4 @@ typedef struct cl_clientfuncs_s {
     void (*CLIENTFACTORY)(void);
 } cl_clientfunc_t;
 
-#endif /* _SDK_H */
+#endif /* SDK_H_ */
diff --git a/src/include/util.h b/src/include/util.h
index 4dd60e7..69856c9 100644
--- a/src/include/util.h
+++ b/src/include/util.h
@@ -1,5 +1,5 @@
-#ifndef _UTIL_H
-#define _UTIL_H
+#ifndef UTIL_H_
+#define UTIL_H_
 
 #include "sdk.h"
 #include "globals.h"
@@ -15,4 +15,4 @@ char* get_name(int ent_idx);
 bool vec_is_zero(vec3_t v);
 bool world_to_screen(vec3_t vec, vec2_t screen);
 
-#endif /* _UTIL_H */
+#endif /* UTIL_H_ */