You will find the answer to your question on their website in the " about us " career section...
There is a difference if you are type rated or not.
Type rated : ICAO with type rating within the last 24 months
English language proficiency level 4 or above
1500 Hours total time
500 Hours B737 300-900
Non type rated : Same as above for the first 2
2500 Hours total time
1000 Hours on Efis aircraft above 10 tonnes
There are other conditions that you can check on the website for the full détails.
Cheers.