sysHttpStatRespBucket1k SNMP metrics meaning

Hi,

I would like to get information about few of the exposed SNMP metrics which description is very unclear...

sysHttpStatRespBucket1k with oid 1.3.6.1.4.1.3375.2.1.1.2.4.17

sysHttpStatRespBucket4k with oid 1.3.6.1.4.1.3375.2.1.1.2.4.18

If we take sysHttpStatRespBucket1k, I found following description "The number of responses under 1k." but are we talking of a HTTP response size or a duration?

Thanks for light anyone could provide on this topic.