silverline propane torch instructions?

Please can anyone offer guidance or relate their experience of:

Silverline general purpose propane torch model 456996 - Supplied with 2 interchangeable gas jets and 3 burners: 25, 35 and

This is a replacement for my trusty but aged Sievert torch. Application: plumbing/Cu soldering.

My main query is: Which gas jet goes with which burner? The torch is supplied without assembly or usage instructions.

Bought on ebay but the ultimate suppplier

Any thoughts most appreciated.

TIA