Asked the question on another forum & got this back
"looks the same as this one. doesn't mention charging but as it's portable I reckon 12V. Little black thing looks like a 12v port
https://bugzapperlamps.com.au/product/bug-sentinel-bug-zapper-portable-rechargeable-cordless/"
Does say "rechargeable design also makes this bug zapper a good choice for camping and caravan trips" so you'd "think" 12V
Can't see any mention of sizes anywhere, but unless those in-use photos are photo-chopped (& they look like they could be ) then it's quite a big unit
Also makes reference to Bunnings, but can't see anything for it on their site
owners manual, assuming that it's the same one, makes no mention of 12v charging. Only 240v.
CHARGING THE BUG ZAPPER
• Turn the ON/OFF dial to the OFF position.
• Plug the adaptor into the port on the bug zapper and into the
240-volt wall socket.
• Charge for 8 hours or until the indicator light above the dial illuminates to indicate
the battery is fully charged.
• Turn ON/OFF dial into ON position to activate the zapper.
• IMPORTANT: The bug zapper UV light will not operate when on charge.
USING THE AC-DC Adaptor
• Turn dial to OFF.
• Plug AC-DC adaptor into the charging port of the bug zapper.
• Plug the other end into any standard 240-volt wall outlet.
https://bugzapperlamps.com.au/wp-content/uploads/2017/12/Bug-Sentinel-Rechargeable-Bug-Zapper-Oct-V1-2018.pdf