Lol beginning to wish I hadn't posted this deal now, so many negative comments!
All I can say is before saying they are unsafe please have a look for yourself and then don't buy if not happy.

IMHO it's not very fair to be so negative about something if you have not actually seen it. After all just because something is cheap does not always mean it is not good nor does paying a high price guarantee quality.

You might like to do a little research on Fire angel alarms, I had 5 installed by the local brigade after a house fire, they all carried a 10 year battery guarantee. All failed in under 3 years; 4 making making an electrical 'arching' sound.
Checking on the web I found lots of people had the same experience with them only lasting a year or so rather than he 10 years quoted. also see this -: http://www.dailymail.co.uk/news/article-2058922/Firefighters-forced-stop-handing-smoke-alarms-catches-alight-nearly-burns-house.html

Would you trust your life with a £1 smoke detector. Wouldn't compromise on something this important. This companies products are never ready.

Picture of the pack opened

I'd ask advice from the fire service, some will be entitled to free ones with 10 year batteries (dependent on budgets due to austerity) but even if you're not I'd buy a reputable brand like Fire Angel or whatever they recommend. B&M's sells some really rubbish electrical goods branded as EverReady and I wouldn't trust mine or my family's life with their stuff.

easy to test with a cigarette or a smoking piece of paper

These are so cheap; they instantly reminded me of the Only Fools And Horses scene at the auction of "smoke-damaged fire alarms".

I don't need to. The majority of fire services still recommend using them and the problem batch was in 2012. I think the fire service are in a better position to research the quality of their products than you or I can via any internet searches. As I said I'd get their advice, maybe a free device as well and if they don't specifically endorse fire angel, that's fine. I just don't expect them to endorse devices specially imported for B&M stores carrying the EverReady brand which is not the EveryReady company that people used to associate with quality batteries. They are poor quality and I would expect anyone sensible who really had personal experience of any smoke alarms that were arcing would go out of their way to get advice & buy the the safest products in the future, whatever they may be! confused

We had a couple fitted by our local fire service, they were Kidde branded supposedly lasting 10 years but neither of them did - they both lasted around 2.5 years before they failed - very surprising considering they had around 3 or 4 chunky lithium batteries inside them.

Lol beginning to wish I hadn't posted this deal now, so many negative comments!
All I can say is before saying they are unsafe please have a look for yourself and then don't buy if not happy.

IMHO it's not very fair to be so negative about something if you have not actually seen it. After all just because something is cheap does not always mean it is not good nor does paying a high price guarantee quality.