diff --git a/lib/GMLIB_API-JS.js b/lib/GMLIB_API-JS.js
index e3cce3d..cd48ed4 100644
--- a/lib/GMLIB_API-JS.js
+++ b/lib/GMLIB_API-JS.js
@@ -2291,14 +2291,14 @@ class GMLIB_BinaryStream {
             this.writeUnsignedVarInt(data.id);
             this.writeUnsignedVarInt(data.type);
             switch (data.type) {
-                case 0: this.writeByte(data.value); break;
-                case 1: this.writeSignedShort(data.value); break;
-                case 2: this.writeSignedInt(data.value); break;
+                case 0: this.writeUnsignedChar(data.value); break;
+                case 1: this.writeUnsignedShort(data.value); break;
+                case 2: this.writeVarInt(data.value); break;
                 case 3: this.writeFloat(data.value); break;
                 case 4: this.writeString(data.value); break;
                 case 5: this.writeCompoundTag(data.value); break;
                 case 6: this.writeBlockPos(data.value); break;
-                case 7: this.writeSignedInt64(data.value); break;
+                case 7: this.writeVarInt64(data.value); break;
                 case 8: this.writeVec3(data.value); break;
                 default: throw new Error("Unknown data type");
             }