I use both when it’s attached to a bag
I’ll give that a go, but very much doubt the rubber strap will fit through the loop on one of my bags. I’d also perhaps wrongly assumed i’d not get enough tension on the strap to keep it clipped on without a post to wrap around.
Need to bodge a new rubber bung to make it watertight first (yes, I know you can buy new ones, but after P&P added it would cost more than the light did!)
Regarding the Zecto – how weather resistant are you finding it? Lots of reports of water ingress on reviews