diff --git a/.gitignore b/.gitignore
index 0b63bf4..58db492 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,3 +9,5 @@ tmp
 Gemfile.lock
 .idea/*
 .rbx/
+.ruby-version
+.ruby-gemset
diff --git a/lib/httpi/adapter/curb.rb b/lib/httpi/adapter/curb.rb
index 99fc3b0..19924a5 100644
--- a/lib/httpi/adapter/curb.rb
+++ b/lib/httpi/adapter/curb.rb
@@ -121,12 +121,14 @@ def setup_ssl_auth
         end
 
         @client.ssl_version = case ssl.ssl_version
-          when :TLSv1_2 then 1
-          when :TLSv1_1 then 1
-          when :TLSv1   then 1
-          when :SSLv2   then 2
-          when :SSLv23  then 2
-          when :SSLv3   then 3
+          when :TLSv1_2 then ::Curl::CURL_SSLVERSION_TLSv1_2
+          when :TLSv1_1 then ::Curl::CURL_SSLVERSION_TLSv1_1
+          when :TLSv1_0 then ::Curl::CURL_SSLVERSION_TLSv1_0
+          when :TLSv1   then ::Curl::CURL_SSLVERSION_TLSv1
+          when :SSLv2   then ::Curl::CURL_SSLVERSION_SSLv2
+          when :SSLv23  then ::Curl::CURL_SSLVERSION_SSLv2
+          when :SSLv3   then ::Curl::CURL_SSLVERSION_SSLv3
+          else ::Curl::CURL_SSLVERSION_DEFAULT
         end
       end
 
diff --git a/lib/httpi/auth/ssl.rb b/lib/httpi/auth/ssl.rb
index f998a5a..1c87e4d 100644
--- a/lib/httpi/auth/ssl.rb
+++ b/lib/httpi/auth/ssl.rb
@@ -11,14 +11,21 @@ class SSL
       VERIFY_MODES = [:none, :peer, :fail_if_no_peer_cert, :client_once]
       CERT_TYPES = [:pem, :der]
 
-      # Fix for
-      # httpi/auth/ssl.rb:13: warning: constant OpenSSL::SSL::SSLContext::METHODS is deprecated
-      ssl_context = OpenSSL::SSL::SSLContext
-      SSL_VERSIONS = if ssl_context.const_defined? :METHODS_MAP
-        ssl_context.const_get(:METHODS_MAP).keys
-      else
-        ssl_context::METHODS.reject { |method| method.match(/server|client/) }
-      end.sort.reverse
+      # A default set of possible SSL protocols httpi should try to have support for.
+      # Note: Not all adapters may support all listed versions.
+      SSL_VERSIONS = [:SSLv23, :SSLv2, :SSLv3, :TLSv1, :TLSv1_0, :TLSv1_1, :TLSv1_2]
+
+      # All supported OpenSSL protocols.
+      # Used in case of OpenSSL support unexpected protocol which is not listed in SSL_VERSIONS.
+      OPENSSL_ALL_VERSIONS = begin
+        ssl_context = OpenSSL::SSL::SSLContext
+        # Avoid "warning: constant OpenSSL::SSL::SSLContext::METHODS is deprecated" message
+        if ssl_context.const_defined? :METHODS_MAP
+          ssl_context.const_get(:METHODS_MAP).keys
+        else
+          ssl_context::METHODS.reject { |method| method.match(/server|client/) }
+        end
+      end
 
       # Returns whether SSL configuration is present.
       def present?
@@ -82,7 +89,7 @@ def ssl_version
 
       # Sets the SSL version number. Expects one of <tt>HTTPI::Auth::SSL::SSL_VERSIONS</tt>.
       def ssl_version=(version)
-        unless SSL_VERSIONS.include? version
+        unless SSL_VERSIONS.include?(version) || OPENSSL_ALL_VERSIONS.include?(version)
           raise ArgumentError, "Invalid SSL version #{version.inspect}\n" +
                                "Please specify one of #{SSL_VERSIONS.inspect}"
         end
diff --git a/spec/httpi/adapter/curb_spec.rb b/spec/httpi/adapter/curb_spec.rb
index ec931b7..6422043 100644
--- a/spec/httpi/adapter/curb_spec.rb
+++ b/spec/httpi/adapter/curb_spec.rb
@@ -251,15 +251,14 @@
         end
 
         context 'sets ssl_version' do
-          it 'defaults to nil when no ssl_version is specified' do
-            curb.expects(:ssl_version=).with(nil)
+          it 'defaults to 0 when no ssl_version is specified' do
+            curb.expects(:ssl_version=).with(0)
             adapter.request(:get)
           end
 
           it 'to 1 when ssl_version is specified as TLSv1' do
             request.auth.ssl.ssl_version = :TLSv1
             curb.expects(:ssl_version=).with(1)
-
             adapter.request(:get)
           end
 
@@ -267,14 +266,30 @@
             version = HTTPI::Auth::SSL::SSL_VERSIONS.select { |method| method.to_s.match(/SSLv2|SSLv23/) }.first
             request.auth.ssl.ssl_version = version
             curb.expects(:ssl_version=).with(2)
-
             adapter.request(:get)
           end
 
           it 'to 3 when ssl_version is specified as SSLv3' do
             request.auth.ssl.ssl_version = :SSLv3
             curb.expects(:ssl_version=).with(3)
+            adapter.request(:get)
+          end
+
+          it 'to 4 when ssl_version is specified as TLSv1_0' do
+            request.auth.ssl.ssl_version = :TLSv1_0
+            curb.expects(:ssl_version=).with(4)
+            adapter.request(:get)
+          end
+
+          it 'to 5 when ssl_version is specified as TLSv1_1' do
+            request.auth.ssl.ssl_version = :TLSv1_1
+            curb.expects(:ssl_version=).with(5)
+            adapter.request(:get)
+          end
 
+          it 'to 6 when ssl_version is specified as TLSv1_2' do
+            request.auth.ssl.ssl_version = :TLSv1_2
+            curb.expects(:ssl_version=).with(6)
             adapter.request(:get)
           end
         end