Any difference with these 2 types of RAM

[Night201]

1
2

 

[flibidyflob]

I think I'd pose that question to ZZF because I don't see the KVR400AK2/1GR product listed here but you will find the KVR400X64C3AK2/1G in that listing. The assumption is that they have different timings but the shorter part number doesn't give a hint as to what it might be although in ZZF larger product image it appears to be CL2.5 instead of 3.