diff --git a/libraries/AP_Compass/AP_Compass_HIL.h b/libraries/AP_Compass/AP_Compass_HIL.h
index b3cb985d91..982e72bb28 100644
--- a/libraries/AP_Compass/AP_Compass_HIL.h
+++ b/libraries/AP_Compass/AP_Compass_HIL.h
@@ -7,7 +7,7 @@
 class AP_Compass_HIL : public Compass
 {
   public:
-	AP_Compass_HIL(AP_Var::Key key = AP_Var::k_key_none) : Compass(key) { product_id = AP_COMPASS_TYPE_HIL; }
+	AP_Compass_HIL() : Compass() { product_id = AP_COMPASS_TYPE_HIL; }
 	bool read(void);
 	void setHIL(float Mag_X, float Mag_Y, float Mag_Z);
 };
diff --git a/libraries/AP_Compass/AP_Compass_HMC5843.cpp b/libraries/AP_Compass/AP_Compass_HMC5843.cpp
index 6a160230bd..12809d74a8 100644
--- a/libraries/AP_Compass/AP_Compass_HMC5843.cpp
+++ b/libraries/AP_Compass/AP_Compass_HMC5843.cpp
@@ -75,7 +75,7 @@ bool AP_Compass_HMC5843::write_register(uint8_t address, byte value)
   the 5883L has a different orientation to the 5843. This allows us to
   use a single MAG_ORIENTATION for both
  */
-static void rotate_for_5883L(AP_VarS<Matrix3f> *_orientation_matrix)
+static void rotate_for_5883L(AP_Matrix3f *_orientation_matrix)
 {
 		_orientation_matrix->set_and_save(_orientation_matrix->get() * Matrix3f(ROTATION_YAW_90));
 }
diff --git a/libraries/AP_Compass/AP_Compass_HMC5843.h b/libraries/AP_Compass/AP_Compass_HMC5843.h
index 2549f38a8f..d5ef7e967d 100644
--- a/libraries/AP_Compass/AP_Compass_HMC5843.h
+++ b/libraries/AP_Compass/AP_Compass_HMC5843.h
@@ -56,7 +56,7 @@ class AP_Compass_HMC5843 : public Compass
     uint32_t _retry_time; // when unhealthy the millis() value to retry at
 
   public:
-	AP_Compass_HMC5843(AP_Var::Key key = AP_Var::k_key_none) : Compass(key) {}
+	AP_Compass_HMC5843() : Compass() {}
 	virtual bool init(void);
 	virtual bool read(void);
 	virtual void set_orientation(const Matrix3f &rotation_matrix);
diff --git a/libraries/AP_Compass/Compass.cpp b/libraries/AP_Compass/Compass.cpp
index 4d5d69a9c4..848de698d0 100644
--- a/libraries/AP_Compass/Compass.cpp
+++ b/libraries/AP_Compass/Compass.cpp
@@ -1,15 +1,19 @@
 /// -*- tab-width: 4; Mode: C++; c-basic-offset: 4; indent-tabs-mode: nil -*-
 #include "Compass.h"
 
+const AP_Param::GroupInfo Compass::var_info[] PROGMEM = {
+	{ AP_PARAM_MATRIX3F, "",     VAROFFSET(Compass, _orientation_matrix) },
+	{ AP_PARAM_VECTOR3F, "",     VAROFFSET(Compass, _offset) },
+	{ AP_PARAM_VECTOR3F, "DEC",  VAROFFSET(Compass, _declination) },
+	{ AP_PARAM_NONE, "" }
+};
+
 // Default constructor.
 // Note that the Vector/Matrix constructors already implicitly zero
 // their values.
 //
-Compass::Compass(AP_Var::Key key) :
-    _group(key, PSTR("COMPASS_")),
-    _orientation_matrix	(&_group, 0),
-    _offset				(&_group, 1),
-    _declination		(&_group, 2, 0.0, PSTR("DEC")),
+Compass::Compass(void) :
+    _declination		(0.0),
     _null_init_done(false),
     _null_enable(false),
 	product_id(AP_COMPASS_TYPE_UNKNOWN)
@@ -50,7 +54,7 @@ Compass::save_offsets()
 Vector3f &
 Compass::get_offsets()
 {
-    return _offset.get();
+    return _offset;
 }
 
 void
@@ -183,4 +187,4 @@ Compass::null_offsets_disable(void)
 {
 	_null_init_done = false;
 	_null_enable = false;
-}
\ No newline at end of file
+}
diff --git a/libraries/AP_Compass/Compass.h b/libraries/AP_Compass/Compass.h
index 67a533fb02..897068c490 100644
--- a/libraries/AP_Compass/Compass.h
+++ b/libraries/AP_Compass/Compass.h
@@ -47,7 +47,7 @@ public:
 	///
 	/// @param  key         Storage key used for configuration data.
 	///
-	Compass(AP_Var::Key key);
+	Compass();
 
 	/// Initialize the compass device.
 	///
@@ -132,10 +132,11 @@ public:
 	virtual void set_declination(float radians);
 	float get_declination();
 
+    static const struct AP_Param::GroupInfo var_info[];
+
 protected:
-	AP_Var_group        _group;                 ///< storage group holding the compass' calibration data
-	AP_VarS<Matrix3f>   _orientation_matrix;
-	AP_VarS<Vector3f>   _offset;
+	AP_Matrix3f         _orientation_matrix;
+	AP_Vector3f         _offset;
 	AP_Float            _declination;
 
 	bool                _null_enable;        	///< enabled flag for offset nulling