Number range in batch manament

Hi,

I have setup batch level as Material but not maintained any number range in BATCH_MAT ,one standard number range is in BATCH_CLT and for any material in that plant this number range is getting consumed (134,135,136....).

Does that mean batch would be still unique at client level irrespective of level selected ?

Also there is no external number range present still I can create batch manually like A000001,A000002 is this standard behaviour, if yes then why external no range maintenance option is there.