diff --git a/lib/services/address/index.js b/lib/services/address/index.js
index d08ddc3e..75878d70 100644
--- a/lib/services/address/index.js
+++ b/lib/services/address/index.js
@@ -50,9 +50,9 @@ AddressService.dependencies = [
 ];
 
 AddressService.PREFIXES = {
-  OUTPUTS: new Buffer('02', 'hex'),
-  SPENTS: new Buffer('03', 'hex'),
-  SPENTSMAP: new Buffer('05', 'hex')
+  OUTPUTS: new Buffer('02', 'hex'), // Query outputs by address and/or height
+  SPENTS: new Buffer('03', 'hex'), // Query inputs by address and/or height
+  SPENTSMAP: new Buffer('05', 'hex') // Get the input that spends an output
 };
 
 AddressService.SPACER_MIN = new Buffer('00', 'hex');