diff --git a/tunnels.cfg.md b/tunnels.cfg.md
index 0196be1..0cd2792 100644
--- a/tunnels.cfg.md
+++ b/tunnels.cfg.md
@@ -1,6 +1,7 @@
 tunnels.cfg is designed to support multiple I2P tunnels.  
 Must be located in ~/.i2pd.  
 
+.ini file format.  
 Consists of multiple sections with unique name each.
 Section type is specified by 'type' parameter  with possible values 'client' or 'server'. 
 Each 'client' specifies I2P client tunnel and each 'server' specifies I2P server tunnel.