diff --git a/lib/http/form_data/multipart.rb b/lib/http/form_data/multipart.rb
index b7c387e..ed10c56 100644
--- a/lib/http/form_data/multipart.rb
+++ b/lib/http/form_data/multipart.rb
@@ -54,7 +54,7 @@ def tail
       end
 
       def parts(data)
-        return Param.coerce_array_of_pairs data if data.is_a?(Array)
+        return Param.coerce data if data.is_a?(Array)
         Param.coerce FormData.ensure_hash data
       end
     end
diff --git a/lib/http/form_data/multipart/param.rb b/lib/http/form_data/multipart/param.rb
index 0b19b22..b96c574 100644
--- a/lib/http/form_data/multipart/param.rb
+++ b/lib/http/form_data/multipart/param.rb
@@ -40,11 +40,11 @@ def initialize(name, value)
           @io = CompositeIO.new [header, @part, footer]
         end
 
-        # Flattens given `data` Hash into an array of `Param`'s.
+        # Flattens given `data` Hash or Array into an array of `Param`'s.
         # Nested array are unwinded.
         # Behavior is similar to `URL.encode_www_form`.
         #
-        # @param [Hash] data
+        # @param [Array || Hash] data
         # @return [Array<FormData::MultiPart::Param>]
         def self.coerce(data)
           params = []
@@ -57,25 +57,6 @@ def self.coerce(data)
           params
         end
 
-         # Flattens given Array of `data` Array pairs into an array of `Param`'s.
-        # Nested array are unwinded.
-        # Behavior is similar to `URL.encode_www_form`.
-        #
-        # @param [Array] data
-        # @return [Array<FormData::MultiPart::Param>]
-        def self.coerce_array_of_pairs(data)
-          params = []
-
-          data.each do |pair|
-            name, values = pair
-            Array(values).each do |value|
-              params << new(name, value)
-            end
-          end
-
-          params
-        end
-
         private
 
         def header