Complex sentence: The song was their third number-one on the Mainstream Rock chart, allowing them to tie with The Pretty Reckless to have the most number-ones on that chart by a band led by a female vocalist.
Split into simpler sentences: The song was their third number-one on the Mainstream Rock chart. This allows the band to tie with The Pretty Reckless to have the most number-ones on that chart by a band led by a female vocalist.