60/40 tin-lead solders can be used to join copper, copper alloys, lead, nickel alloys, steel and may be found in general applications such as electrical/components, radiators, stained glass and many low melting range needs. Exceptions; Tin-lead solders are not to be used in potable water systems or not recommended for joints subject to high stress or vibration in the cooling industry due to lack of sufficient elongation properties. Solid solders will need a soldering flux or we also offer solders with rosin or acid flux cored. Similar to 50/50 but flows faster due to narrow melting range making it ideal for delicate work. CAUTION these are lead-bearing solders making it illegal to use lead solders in ALL public or private potable water systems