diff --git a/README.md b/README.md
index 823c8a7..d1bd33f 100644
--- a/README.md
+++ b/README.md
@@ -12,10 +12,26 @@ with a .cpp or .h file as filename to open a new tab containing a vertical split
 with the corresponding header file in the left window and the corresponding
 source file in the right window.
 
+Use
+
+	:Split
+
+to open the corresponding header or source file to your currently open file in
+a vertical split.
+
 ## Configuration
 
 You can configure the following settings:
 
+### g:splitopen_extensions
+
+Use this dictionary to define your pairs of left-hand- right-hand-side file
+types. E.g.
+
+	let g:splitopen_extensions = {"h": "cpp"}
+
+always places a .cpp file on the right-hand side when opening an .h file and
+vice versa.
 
 ### g:splitopen_set_fzf_keys
 
@@ -32,6 +48,15 @@ SplitOpen is GPL-3.0 licensed. See LICENSE file for more info.
 
 ## Changelog 
 
+v1.1.0
+* Added Split() command
+
+v1.0.0
+* Fixed error when reloading plugin
+
+v0.0.4
+* Add filetype configuraton
+
 v0.0.3
 * Add fzf.vim keybinding
 
diff --git a/autoload/splitopen.vim b/autoload/splitopen.vim
index d4f2aac..1151120 100644
--- a/autoload/splitopen.vim
+++ b/autoload/splitopen.vim
@@ -1,11 +1,68 @@
-function splitopen#SplitOpenFile(filename)
-	execute("tabedit " . a:filename)
-	let l:file_extension = tolower(fnamemodify(a:filename, ":e"))
-	if l:file_extension == "cpp"
-		execute("FSSplitLeft")
-		execute("wincmd l")
-	elseif l:file_extension == "h"
-		execute("FSSplitRight")
-		execute("wincmd h")
+function s:invert_dict(source_dict)
+	let result = {}
+	for [key, value] in items(a:source_dict)
+		let result[value] = key
+	endfor
+	return result
+endfunction
+
+let s:extensions = g:splitopen_extensions
+let s:extensions_rev = s:invert_dict(s:extensions)
+
+function s:isLeftSideExtension(extension)
+	return has_key(s:extensions, a:extension)
+endfunction
+
+function s:isRightSideExtension(extension)
+	return has_key(s:extensions_rev, a:extension)
+endfunction
+
+function s:getFileExtension(filename)
+	return fnamemodify(a:filename, ":e")
+endfunction
+
+function s:getFileRoot(filename)
+	return fnamemodify(a:filename, ":r")
+endfunction
+
+function s:getSwitchExtension(filename)
+	let extension = s:getFileExtension(a:filename)
+	if s:isLeftSideExtension(extension)
+		return s:extensions[extension]
+	elseif s:isRightSideExtension(extension)
+		return s:extensions_rev[extension]
 	endif
 endfunction
+
+function s:getSwitchFile(filename)
+	return s:getFileRoot(a:filename) . "." . s:getSwitchExtension(a:filename)
+endfunction
+
+function s:addLeftSplit(filename)
+	execute("vsplit " . s:getSwitchFile(a:filename))
+	execute("wincmd l")
+endfunction
+
+function s:addRightSplit(filename)
+	execute("vsplit " . s:getSwitchFile(a:filename))
+	execute("wincmd L")
+	execute("wincmd h")
+endfunction
+
+function s:splitOpenFile(filename)
+	let extension = s:getFileExtension(a:filename)
+	if s:isLeftSideExtension(extension)
+		call s:addRightSplit(a:filename)
+	elseif s:isRightSideExtension(extension)
+		call s:addLeftSplit(a:filename)
+	endif
+endfunction
+
+function! splitopen#SplitOpenFile(filename)
+	execute("tabedit " . a:filename)
+	call s:splitOpenFile(a:filename)
+endfunction
+
+function! splitopen#SplitFile()
+	call s:splitOpenFile(expand("%:p"))
+endfunction
diff --git a/doc/splitopen.txt b/doc/splitopen.txt
index c4b3e6e..8d64698 100644
--- a/doc/splitopen.txt
+++ b/doc/splitopen.txt
@@ -5,7 +5,8 @@ CONTENTS                                                     *SplitOpenContents*
 
 	1. Usage ..............................|SplitOpenUsage|
 	2. Configuration ......................|SlitOpenConfiguraton|
-		2.1 g:splitopen_set_fzf_keys.......|SplitOpenConfiguration_set_fzf_keys|
+		2.1 g:splitopen_extensions.........|SplitOpenConfiguration_extensions|
+		2.2 g:splitopen_set_fzf_keys.......|SplitOpenConfiguration_set_fzf_keys|
 	3. License ............................|SplitOpenLicense|
 	4. Changelog ..........................|SplitOpenChangelog|
 
@@ -20,14 +21,31 @@ with a .cpp or .h file as filename to open a new tab containing a vertical split
 with the corresponding header file in the left window and the corresponding
 source file in the right window.
 
+Use
+
+	:Split
+
+to open the corresponding header or source file to your currently open file in
+a vertical split.
+
 ================================================================================
 2. Configuration                                        *SplitOpenConfiguration*
 
 You can configure the following settings:
 
 --------------------------------------------------------------------------------
+2.1 g:splitopen_extensions                   *SplitOpenConfiguration_extensions*
 
-2.1 g:splitopen_set_fzf_keys               *SplitOpenConfiguration_set_fzf_keys*
+Use this dictionary to define your pairs of left-hand- right-hand-side file
+types. E.g.
+
+	let g:splitopen_extensions = {"h": "cpp"}
+
+always places a .cpp file on the right-hand side when opening an .h file and
+vice versa.
+
+--------------------------------------------------------------------------------
+2.2 g:splitopen_set_fzf_keys               *SplitOpenConfiguration_set_fzf_keys*
 
 Set this option to 1 
 
@@ -44,6 +62,12 @@ SplitOpen is GPL-3.0 licensed. See LICENSE file for more info.
 ================================================================================
 4. Changelog                                                *SplitOpenChangelog*
 
+v1.1.0
+	* Added Split() command
+v1.0.0
+	* Fixed error when reloading plugin
+v0.0.4
+	* Add filetype configuraton
 v0.0.3
 	* Add fzf.vim keybinding
 v0.0.2
diff --git a/plugin/splitopen.vim b/plugin/splitopen.vim
index 91cabdd..2534fdb 100644
--- a/plugin/splitopen.vim
+++ b/plugin/splitopen.vim
@@ -1,4 +1,13 @@
-command -nargs=1 SplitOpen :call splitopen#SplitOpenFile("<args>")
+command! -nargs=1 SplitOpen :call splitopen#SplitOpenFile("<args>")
+command! Split :call splitopen#SplitFile()
+
+" map left-split / right-split file extensions
+if !exists("g:splitopen_extensions")
+	let g:splitopen_extensions = {
+		\	"h": "cpp",
+		\	"H": "CPP",
+		\	}
+endif
 
 if !exists('g:splitopen_set_fzf_keys')
 	let g:splitopen_set_fzf_keys = 0
@@ -9,5 +18,6 @@ if g:splitopen_set_fzf_keys
 		\	'ctrl-s': 'SplitOpen',
 		\	'ctrl-t': 'tab split',
 		\ 	'ctrl-x': 'split',
-		\ 	'ctrl-v': 'vsplit' }
+		\ 	'ctrl-v': 'vsplit',
+		\	}
 endif