use length from wordlist

[amdeusace]

hashcat-5.1.0>hashcat64 -m 2500 -a 6 --session optus_session optus.hccapx 5letters.txt 5letters.txt ?d?d?d?d?d

that one tries to make 5letters.txt + numbers
but i would like to get 5letters.txt + 5letters.txt +numbers

any help?