diff --git a/docs/ServiceList.md b/docs/ServiceList.md
index 25c7562..d41692e 100644
--- a/docs/ServiceList.md
+++ b/docs/ServiceList.md
@@ -4,7 +4,7 @@ HomeSpan implements all [HAP-R2](https://developer.apple.com/support/homekit-acc
 
 HomeSpan Services and Characteristics are implemented as C++ Classes with names that exactly match the spelling and capitalization specified by Apple in Sections 8  and 9 of [HAP-R2](https://developer.apple.com/support/homekit-accessory-protocol/), but without any spaces.  HomeSpan Services are defined in HomeSpan's `Service` namespace.  HomeSpan Characteristics are defined in HomeSpan's `Characteristic` namespace.  For example, HomeSpan defines the *Carbon Dioxide Sensor* Service (HAP Service 8.7) as `Service::CarbonDioxideSensor`, and the *Carbon Dioxide Detected* Characteristic (HAP Characteristic 9.16) as `Characteristic::CarbonDioxideDetected`.
 
-HomeSpan Services and Characteristics are instantiated with a C++ `new` command.  Services do not take any arguments, whereas Characteristics take a single, optional argument that is used to initialize the value of the Characteristic at startup.  If this argument is not specified, HomeSpan will apply a reasonable default value based on the Characteristic's type and allowed range.
+HomeSpan Services and Characteristics are instantiated with a C++ `new` command.  Services do not take any arguments, whereas Characteristics take a single, optional argument that is used to initialize the value of the Characteristic at startup.  If this argument is not specified, HomeSpan will apply a reasonable [default value](#characteristic-types-and-defaults) based on the Characteristic's type and allowed range.
 
 A list of all HomeSpan Services is provided in the table below.  For each Service the table also indicates which Characteristics are required and which are optional.  For example, a dimmable light bulb could be configured in HomeSpan as such:
 
@@ -62,6 +62,8 @@ Additionally, when first starting up, HomeSpan begins by validating the device's
 | Window | CurrentPosition<br>TargetPosition<br>PositionState | Name<br>HoldPosition<br>ObstructionDetected |
 | WindowCovering | CurrentPosition<br>TargetPosition<br>PositionState | Name<br>HoldPosition<br>CurrentHorizontalTiltAngle<br>TargetHorizontalTiltAngle<br>CurrentVerticalTiltAngle<br>TargetVerticalTiltAngle<br>ObstructionDetected |
 
+
+### Characteristic Types and Defaults
 ---
 
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