diff --git a/Source/Meadow.Foundation.Core/Sensors/Spatial/IDistanceSensor.cs b/Source/Meadow.Foundation.Core/Sensors/Spatial/IDistanceSensor.cs
deleted file mode 100644
index aac03490dc..0000000000
--- a/Source/Meadow.Foundation.Core/Sensors/Spatial/IDistanceSensor.cs
+++ /dev/null
@@ -1,14 +0,0 @@
-using System;
-namespace Meadow.Foundation.Sensors.Spatial
-{
-    /// <summary>
-    /// Interface for distance sensors
-    /// </summary>
-    public interface IDistanceSensor
-    {
-        /// <summary>
-        /// Distance from sensor to object
-        /// </summary>
-        Units.Length Distance { get; }   
-    }
-}
diff --git a/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Driver/MaxBotix.Analog.cs b/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Driver/MaxBotix.Analog.cs
index 044ea63c88..0259fa5982 100644
--- a/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Driver/MaxBotix.Analog.cs
+++ b/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Driver/MaxBotix.Analog.cs
@@ -44,10 +44,10 @@ void AnalogInitialize()
                         ChangeResult<Length> changeResult = new ChangeResult<Length>()
                         {
                             New = await ReadSensorAnalog(),
-                            Old = Length,
+                            Old = Distance,
                         };
                         // save state
-                        Length = changeResult.New;
+                        Distance = changeResult.New;
                         // notify
                         RaiseEventsAndNotify(changeResult);
                     }
diff --git a/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Driver/MaxBotix.Serial.cs b/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Driver/MaxBotix.Serial.cs
index 70e2dec92d..2d66b539f6 100644
--- a/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Driver/MaxBotix.Serial.cs
+++ b/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Driver/MaxBotix.Serial.cs
@@ -28,7 +28,7 @@ public MaxBotix(ISerialMessagePort serialMessage, SensorType sensor)
 
         Length ReadSensorSerial()
         {   //I think we'll just cache it for serial
-            return Length.Value;
+            return Distance.Value;
         }
 
         private void SerialMessagePort_MessageReceived(object sender, SerialMessageData e)
@@ -53,10 +53,10 @@ private void SerialMessagePort_MessageReceived(object sender, SerialMessageData
             ChangeResult<Length> changeResult = new ChangeResult<Length>()
             {
                 New = new Length(value, units),
-                Old = Length,
+                Old = Distance,
             };
             // save state
-            Length = changeResult.New;
+            Distance = changeResult.New;
             // notify
             RaiseEventsAndNotify(changeResult);
         }
diff --git a/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Driver/MaxBotix.cs b/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Driver/MaxBotix.cs
index 7a644c87ea..7512c8234c 100644
--- a/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Driver/MaxBotix.cs
+++ b/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Driver/MaxBotix.cs
@@ -1,28 +1,29 @@
-using Meadow.Units;
+using Meadow.Peripherals.Sensors;
+using Meadow.Units;
 using System;
 using System.Threading.Tasks;
 
 namespace Meadow.Foundation.Sensors.Distance
 {
-    public partial class MaxBotix : ByteCommsSensorBase<Length>
+    public partial class MaxBotix : ByteCommsSensorBase<Length>, IRangeFinder
     {
         /// <summary>
         /// Raised when the value of the reading changes.
         /// </summary>
-        public event EventHandler<IChangeResult<Length>> LengthUpdated = delegate { };
+        public event EventHandler<IChangeResult<Length>> DistanceUpdated = delegate { };
 
         /// <summary>
         /// Distance from sensor to object
         /// </summary>
-        public Length? Length { get; protected set; }
+        public Length? Distance { get; protected set; }
 
         /// <summary>
         /// voltage common collector (VCC) typically 3.3V
         /// </summary>
         public double VCC { get; set; } = 3.3;
 
-        CommunicationType communication;
-        SensorType sensorType;
+        readonly CommunicationType communication;
+        readonly SensorType sensorType;
 
         /// <summary>
         /// Read the distance from the sensor
@@ -46,7 +47,7 @@ protected override async Task<Length> ReadSensor()
         /// <param name="changeResult"></param>
         protected override void RaiseEventsAndNotify(IChangeResult<Length> changeResult)
         {
-            LengthUpdated?.Invoke(this, changeResult);
+            DistanceUpdated?.Invoke(this, changeResult);
             base.RaiseEventsAndNotify(changeResult);
         }
 
diff --git a/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Samples/MaxBotix_Sample/MeadowApp.cs b/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Samples/MaxBotix_Sample/MeadowApp.cs
index 79b62e1bfe..930bfd6a10 100644
--- a/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Samples/MaxBotix_Sample/MeadowApp.cs
+++ b/Source/Meadow.Foundation.Peripherals/Sensors.Distance.MaxBotix/Samples/MaxBotix_Sample/MeadowApp.cs
@@ -46,12 +46,12 @@ public MeadowApp()
 
             maxBotix.Subscribe(consumer);
 
-            maxBotix.LengthUpdated += MaxBotix_LengthUpdated;
+            maxBotix.DistanceUpdated += MaxBotix_DistanceUpdated;
 
             maxBotix.StartUpdating(new TimeSpan(0, 0, 1));
         }
 
-        private void MaxBotix_LengthUpdated(object sender, IChangeResult<Length> e)
+        private void MaxBotix_DistanceUpdated(object sender, IChangeResult<Length> e)
         {
             Console.WriteLine($"Length: {e.New.Centimeters}cm");
         }
diff --git a/Source/Meadow.Foundation.Peripherals/Sensors.Distance.Mb10x0/Driver/Mb10x0.cs b/Source/Meadow.Foundation.Peripherals/Sensors.Distance.Mb10x0/Driver/Mb10x0.cs
index 50f50f5bd1..e06862b580 100644
--- a/Source/Meadow.Foundation.Peripherals/Sensors.Distance.Mb10x0/Driver/Mb10x0.cs
+++ b/Source/Meadow.Foundation.Peripherals/Sensors.Distance.Mb10x0/Driver/Mb10x0.cs
@@ -7,7 +7,7 @@
 
 namespace Meadow.Foundation.Sensors.Distance
 {
-    // TODO: why is `DistanceUpdated` never invoked? is this sensor done?
+    // In progress and not working - DistanceUpdated currently is never called 
     public class Mb10x0 : SensorBase<Length>, IRangeFinder
     {
         //==== events
diff --git a/Source/Meadow.Foundation.Peripherals/Sensors.Distance.Sfsr02/Driver/Sfsr02.cs b/Source/Meadow.Foundation.Peripherals/Sensors.Distance.Sfsr02/Driver/Sfsr02.cs
index 4e5d108a12..004453b08e 100644
--- a/Source/Meadow.Foundation.Peripherals/Sensors.Distance.Sfsr02/Driver/Sfsr02.cs
+++ b/Source/Meadow.Foundation.Peripherals/Sensors.Distance.Sfsr02/Driver/Sfsr02.cs
@@ -12,22 +12,21 @@ namespace Meadow.Foundation.Sensors.Distance
     /// </summary>
     public class Sfsr02: SensorBase<Length>, IRangeFinder
     {
-        //==== events
 		/// <summary>
         /// Raised when an received a rebound trigger signal
         /// </summary>
         public event EventHandler<IChangeResult<Length>> DistanceUpdated;
 
-        //==== internals
         /// <summary>
         /// Trigger/Echo Pin
         /// </summary>
         protected IBiDirectionalPort triggerEchoPort;
 
+        /// <summary>
+        /// Start time
+        /// </summary>
         protected long tickStart;
 
-
-        //==== properties
         /// <summary>
         /// Returns current distance
         /// </summary>
diff --git a/Source/Meadow.Foundation.Peripherals/Sensors.Distance.Vl53l0x/Driver/Vl53l0x.cs b/Source/Meadow.Foundation.Peripherals/Sensors.Distance.Vl53l0x/Driver/Vl53l0x.cs
index 280326ccae..e579e479be 100644
--- a/Source/Meadow.Foundation.Peripherals/Sensors.Distance.Vl53l0x/Driver/Vl53l0x.cs
+++ b/Source/Meadow.Foundation.Peripherals/Sensors.Distance.Vl53l0x/Driver/Vl53l0x.cs
@@ -12,8 +12,14 @@ namespace Meadow.Foundation.Sensors.Distance
     /// </summary>
     public partial class Vl53l0x : ByteCommsSensorBase<Length>, IRangeFinder
     {
+        /// <summary>
+        /// Distance updated event
+        /// </summary>
         public event EventHandler<IChangeResult<Length>> DistanceUpdated = delegate { };
 
+        /// <summary>
+        /// Is the hardware shutdown / off
+        /// </summary>
         public bool IsShutdown
         {
             get
@@ -48,6 +54,12 @@ public bool IsShutdown
        
         byte stopVariable;
 
+        /// <summary>
+        /// Creates a new Vl53l0x object
+        /// </summary>
+        /// <param name="device">Meadow device</param>
+        /// <param name="i2cBus">I2C bus</param>
+        /// <param name="address">I2C address</param>
         public Vl53l0x(
             IDigitalOutputController device, II2cBus i2cBus,
             byte address = (byte)Addresses.Default)
@@ -55,9 +67,14 @@ public Vl53l0x(
         {
         }
 
+        /// <summary>
+        /// Creates a new Vl53l0x object
+        /// </summary>
+        /// <param name="device">Meadow device</param>
         /// <param name="i2cBus">I2C bus</param>
+        /// <param name="shutdownPin">Shutdown pin</param>
         /// <param name="address">VL53L0X address</param>
-        /// <param name="units">Unit of measure</param>
+
         public Vl53l0x(
             IDigitalOutputController device, II2cBus i2cBus, IPin shutdownPin,
             byte address = (byte)Addresses.Default)
@@ -69,6 +86,10 @@ public Vl53l0x(
             Initialize().Wait();
         }
 
+        /// <summary>
+        /// Raise distance change event and notify subscribers
+        /// </summary>
+        /// <param name="changeResult"></param>
         protected override void RaiseEventsAndNotify(IChangeResult<Length> changeResult)
         {
             DistanceUpdated?.Invoke(this, changeResult);
@@ -101,8 +122,6 @@ protected async Task Initialize()
             Peripheral.WriteRegister(0xFF, 0x00);
             Peripheral.WriteRegister(0x80, 0x00);
 
-            //var configControl = (byte)(Read((byte)Register.MsrcConfigControl) | 0x12);
-
             Peripheral.WriteRegister((byte)Register.SystemSequenceConfig, 0xFF);
             var spadInfo = GetSpadInfo();
             int spadCount = spadInfo.Item1;