This is a link to making a fly trap into a SHB trap. Well presented with all the info needed, I have used them for a couple of years and never found a dead bee in them.
Thank you @Peter48. I think you left out the most interesting piece of information, have you found SHB in them? 
I put the liquid thru a sieve once a week and probably average 40 to 50 SHB for each trap, I now only get an odd one in the beetle blaster traps that are between frames in the brood box. The attractant is actually fermented honey and never had a bee in the traps.
But I thought that SHB wasn’t down in your part of WA? Only up in the North?
Cheers
Thank you for details @Peter48. No, we do not have SHB yet. But I think it is only a question of time. And I would rather have knowledge about how to deal with it before it happens.
Good thinking to soak up all you can about them, they arrived from Africa with a team from there for the Sydney Olympics arriving at the RAAF base at Richmond west of Sydney and there was no bio-security there. You would be really pushed, almost impossible to find a hive in the Eastern states free of them.
They are by far our biggest pest in bee keeping here.
Cheers