Are you running an older version of hashcat?
$ hashcat -V
v5.1.0-1569-g74c1bf81+
potfile: PMK * ESSID : PSK
That is exactly the result of the PBKDF2 calculation. It is no longer necessary to pay the price (PBKDF2 calculation time) again if we have a PMK. That will save us GPU time. Also, the calculated PMKs can be used on hashmode 2501, 16801 and 22001 in case we have hashes using the same SALT (ESSID). That will save us more GPU time.
outfile (-o) - only hexyfied if necessary, otherwise in ASCII: MAC_AP : MAC_STA : ESSID : PSK
That is human readable and contain detailed information about the content of the hash.
$ hashcat -V
v5.1.0-1569-g74c1bf81+
potfile: PMK * ESSID : PSK
Code:
5b13d4babb3714ccc62c9f71864bc984efd6a55f237c7a87fc2151e1ca658a9d*ed487162465a774bfba60eb603a39f3a:hashcat!
outfile (-o) - only hexyfied if necessary, otherwise in ASCII: MAC_AP : MAC_STA : ESSID : PSK
Code:
4604ba734d4e:89acf0e761f4:$HEX[ed487162465a774bfba60eb603a39f3a]:hashcat!