Difference between these 2 cameras??

DS-2CE561T-IT3ZE for £70
IRDS-2CD2H43G0-IZS for £240.

Both are varifocal (2.8-12).

I thought as 'IR' is missing at the beginning of the first code I thought it wasnt IR but it's described as 'night and day' 'True IR'.

So why the huge price difference?

Cheers