This looks like a bargain to me - maybe listed on Amazon in error...
I was looking for LED bayonet replacement bulbs and found two listings on Amazon - one listing has the bulb listed as a 12w and the other listed as an 11w - both 75w equivalent replacements.
If you look at the description on both items the specifications are identical:-
Warm White Colour Temperature11 W Input Wattage
Wattage Equivalency 75 W
A+ Energy Efficiency Rated
50,000 Switch Cycles
15,000 Hours Lifetime
15 Years Average Life (at 2.7 hours a day)
Could the listing for the 12w be an error in the title as the 12w are listed @ £23.84 for 4 bulbs and the 11w listing is £23.99 for 6 bulbs...