Weird price difference

[Kobrakai]

Why are these:
http://www.overclockers.co.uk/showproduct.php?prodid=MY-316-CS&groupid=701&catid=8&subcat=

More expensive than these:
http://www.overclockers.co.uk/showproduct.php?prodid=MY-317-CS&groupid=701&catid=8&subcat=1387

Am I missing something obvious?

 

[kmetek]

Corsair Dominator 16GB (4x4GB) PC3-14900C9 1866MHz
Corsair Dominator 16GB (4x4GB) PC3-12800C7 1600MHz

 

[Kobrakai]

But why are the faster ones £22 cheaper?

 

[iTek]

One is CAS 7 and other is CAS 9.

 

[d_brennen]

Ex VAT and inc. VAT mixed up perhaps

 

[Justintime]

But why are the faster ones £22 cheaper?

The CAS 7 memory will be more expensive to produce and may well run 1866MHz speeds at a lower latency than the other kit as the chips are probably better grade, not always true but very likely. I doubt that 1866 kit can run CAS 7 latencies at 1600MHz at the voltages the other kit can.