What is the difference between MFS1S00-HxxxE and MFS1S00-HxxE-LL

Hi,

MFS1S00-HxxxE vs MFS1S00-HxxxE-LL(low latency)
I can’t tell the exact difference even if I look at the specification documents of the two products.
The important thing in IB is low latency, so should I choose MFS1S00-HxxE-LL? I wonder why it is divided into two, and what is the difference and purpose between the two products?