SNS is a feeding tube device provides babies supplemental feeding , it helps in inducing and maintaining lactation by triggering harmonal release. Any practical experience about the nursing system?
Are you seeking information on the use of this specific commercial product (which is expensive) or on the use of feeding tubes at the breast in general? Non-commercial feeding tubes are frequently used.
There are photos of homemade supplementers in the WHO courses on breastfeeding.
If you are writing a paper or doing research take care with the term that you use, Supplementary nursing system (SNS) is a trademarked term for the Medela product. It is not a generic term.