2a- Layer 1 or Physical / Part Number

1- website

2- file show /usr/libdata/fru.models 

3- show chassis hardware models

Mapping between Field Replaceable Units ( FRU ) part numbers and model numbers

https://kb.juniper.net/InfoCenter/index?page=content&id=KB9475

2- file show /usr/libdata/fru.models 

3- show chassis hardware models

can see the part-number with this command:  show chassis hardware models

Can see the SFP with:  show chassis hardware