diff --git a/src/decoders/index.ts b/src/decoders/index.ts
index a7bfd5d..def5275 100644
--- a/src/decoders/index.ts
+++ b/src/decoders/index.ts
@@ -7,7 +7,7 @@ import TrackedPointAccelVelocity from './motion/tracked-point-accel-velocity';
 import TrackedPointPosition from './motion/tracked-point-position';
 import ZoneCollisionDetection from './motion/zone-collision-detection';
 import ZoneObject from './motion/zone-object';
-import RTTrPHeader from './rttrp';
+import RTTrPHeader from './rttrp-header';
 
 export const Decoders = {
   RTTrPHeader,
diff --git a/src/decoders/rttrp.ts b/src/decoders/rttrp-header.ts
similarity index 98%
rename from src/decoders/rttrp.ts
rename to src/decoders/rttrp-header.ts
index 192acf7..167374a 100644
--- a/src/decoders/rttrp.ts
+++ b/src/decoders/rttrp-header.ts
@@ -42,5 +42,6 @@ export default (bytes: Uint8Array): RTTrPHeader => {
     size,
     context,
     subModuleCount,
+    isLittleEndian,
   };
 };
diff --git a/src/models.ts b/src/models.ts
index 2b58719..48ad724 100644
--- a/src/models.ts
+++ b/src/models.ts
@@ -1,5 +1,5 @@
 export type RTTrPHeader = {
-  intHeader?: number;
+  intHeader: number;
   floatHeader: number;
   version: number;
   packetID: number;
@@ -7,6 +7,8 @@ export type RTTrPHeader = {
   size: number;
   context: number;
   subModuleCount: number;
+  isLittleEndian: boolean;
+};
 };
 
 export type TrackableModule =