diff --git a/src/main/java/tsp/headdb/api/Head.java b/src/main/java/tsp/headdb/api/Head.java
index ead2171..5fc5fff 100644
--- a/src/main/java/tsp/headdb/api/Head.java
+++ b/src/main/java/tsp/headdb/api/Head.java
@@ -3,6 +3,7 @@ package tsp.headdb.api;
 import com.mojang.authlib.GameProfile;
 import com.mojang.authlib.properties.Property;
 import org.apache.commons.lang.Validate;
+import org.bukkit.Material;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.SkullMeta;
 import tsp.headdb.database.Category;
@@ -35,7 +36,7 @@ public class Head {
         Validate.notNull(uuid, "uuid must not be null!");
         Validate.notNull(value, "value must not be null!");
 
-        ItemStack item = new ItemStack(XMaterial.PLAYER_HEAD.parseItem());
+        ItemStack item = new ItemStack(Material.PLAYER_HEAD);
         SkullMeta meta = (SkullMeta) item.getItemMeta();
         meta.setDisplayName(Utils.colorize(category != null ? category.getColor() + name : "&8" + name));
         // set skull owner
diff --git a/src/main/java/tsp/headdb/api/LocalHead.java b/src/main/java/tsp/headdb/api/LocalHead.java
index abbe340..fc443e3 100644
--- a/src/main/java/tsp/headdb/api/LocalHead.java
+++ b/src/main/java/tsp/headdb/api/LocalHead.java
@@ -2,6 +2,7 @@ package tsp.headdb.api;
 
 import org.apache.commons.lang.Validate;
 import org.bukkit.Bukkit;
+import org.bukkit.Material;
 import org.bukkit.inventory.ItemStack;
 import org.bukkit.inventory.meta.SkullMeta;
 import tsp.headdb.util.Utils;
@@ -19,7 +20,7 @@ public class LocalHead {
     public ItemStack getItemStack() {
         Validate.notNull(uuid, "uuid must not be null!");
 
-        ItemStack item = new ItemStack(XMaterial.PLAYER_HEAD.parseItem());
+        ItemStack item = new ItemStack(Material.PLAYER_HEAD);
         SkullMeta meta = (SkullMeta) item.getItemMeta();
         meta.setOwningPlayer(Bukkit.getOfflinePlayer(uuid));
         meta.setDisplayName(Utils.colorize("&e" + name));
diff --git a/src/main/java/tsp/headdb/inventory/InventoryUtils.java b/src/main/java/tsp/headdb/inventory/InventoryUtils.java
index bf24ac3..16f7323 100644
--- a/src/main/java/tsp/headdb/inventory/InventoryUtils.java
+++ b/src/main/java/tsp/headdb/inventory/InventoryUtils.java
@@ -15,6 +15,7 @@ import tsp.headdb.util.Utils;
 import tsp.headdb.util.XMaterial;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.List;
 
 public class InventoryUtils {
@@ -150,7 +151,7 @@ public class InventoryUtils {
     public static void openDatabase(Player player) {
         Inventory inventory = Bukkit.createInventory(null, 54, Utils.colorize("&c&lHeadDB &8(" + HeadAPI.getHeads().size() + ")"));
 
-        fill(inventory, XMaterial.BLACK_STAINED_GLASS_PANE.parseItem());
+        fill(inventory, new ItemStack(Material.BLACK_STAINED_GLASS_PANE));
         for (Category category : Category.getCategories()) {
             ItemStack item = category.getItem();
             ItemMeta meta = item.getItemMeta();
@@ -202,13 +203,7 @@ public class InventoryUtils {
     }
 
     private static boolean contains(int n, int... array) {
-        for (int i : array) {
-            if (i == n) {
-                return true;
-            }
-        }
-
-        return false;
+        return Arrays.binarySearch(array, n) > -1;
     }
 
     private static ItemStack buildButton(ItemStack item, String name, String... lore) {
diff --git a/src/main/java/tsp/headdb/inventory/PagedPane.java b/src/main/java/tsp/headdb/inventory/PagedPane.java
index d9783e7..4e71492 100644
--- a/src/main/java/tsp/headdb/inventory/PagedPane.java
+++ b/src/main/java/tsp/headdb/inventory/PagedPane.java
@@ -15,7 +15,6 @@ import org.bukkit.inventory.meta.ItemMeta;
 import tsp.headdb.HeadDB;
 import tsp.headdb.api.HeadAPI;
 import tsp.headdb.util.Utils;
-import tsp.headdb.util.XMaterial;
 
 import java.util.*;
 import java.util.Map.Entry;
@@ -206,7 +205,7 @@ public class PagedPane implements InventoryHolder {
         // create separator
         fillRow(
                 inventory.getSize() / 9 - 2,
-                XMaterial.BLACK_STAINED_GLASS_PANE.parseItem(),
+                new ItemStack(Material.BLACK_STAINED_GLASS_PANE),
                 inventory
         );
 
diff --git a/src/main/resources/plugin.yml b/src/main/resources/plugin.yml
index d73ac3e..2308a61 100644
--- a/src/main/resources/plugin.yml
+++ b/src/main/resources/plugin.yml
@@ -3,6 +3,7 @@ description: ${project.description}
 
 main: tsp.headdb.HeadDB
 version: ${project.version}
+api-version: 1.16
 author: Silent
 
 commands: