3-way or 4-way stopcock?
They look almost identical on the shelf, and both connect three lines, so the natural question for anyone deciding what to stock is whether the 4-way is worth the step up. Most of the time the answer is no, and it helps to know exactly why.
Start with what is the same. Both a 3-way and a 4-way stopcock have three physical ports: an inlet, an outlet and a side port. That is worth saying up front, because the names suggest the 4-way has an extra connection and it does not. What changes is the handle, and how many ways it can route the fluid between those three ports.
What the handle actually does
On a 3-way, the handle turns through roughly 270 degrees and always leaves one of the three ports closed. So at any moment you are sending fluid between two ports while the third sits off. Those three combinations, plus the off, cover the great majority of bedside work: running a line, adding a medication through the side port, drawing a sample, isolating a line.
A 4-way turns a full 360 degrees and gives you a fourth handle position the 3-way simply cannot reach. Depending on the design, that extra position either opens all three ports at once or closes all of them together. That single added state is the entire difference, and it is also the reason the part is called a 4-way. The name counts flow positions, not ports.
The fourth position differs by design, all-open on some 4-way stopcocks and all-off on others. We confirm the exact flow pattern for the configuration you order so it matches how your customers use it.
So which should you stock?
For most buyers, the 3-way is the workhorse and should be the bulk of what you carry. It handles routine infusion, side-port medication and sampling, costs less, and is what most clinicians reach for without thinking. Carry the 4-way for the customers whose procedures actually use that fourth position, and stock it deliberately rather than as a default. Over-ordering 4-ways ties up money in a part that mostly sits in the cupboard while your 3-way stock runs down.
If you are not sure of the split, look at your customer mix. General wards, clinics and most ICU access lean heavily 3-way. The 4-way earns its place where a specific protocol calls for the extra state. When you tell us your mix we can suggest a starting ratio, and because both parts share the same Luer lock, colour-coding, pressure and sterility options, you can keep your range consistent across the two.
Common questions
Both have three physical ports, an inlet, an outlet and a side port. The difference is in how the handle routes flow. A 3-way handle turns through about 270 degrees and always leaves one port closed, so you direct flow between any two of the three. A 4-way handle turns a full 360 degrees and adds a fourth position. Depending on the design, that extra position either opens all three ports together or shuts them all off, which is the capability a 3-way does not have.
The name refers to the number of flow positions, not the number of ports. A 4-way gives you four distinct handle states rather than three, which is where the extra routing option comes from. Both parts physically connect three lines.
When a procedure genuinely uses that fourth position, for example simultaneous access across lines or a single all-off state. For routine IV therapy and most everyday access, a 3-way covers it and is the simpler, lower-cost part. Stock the 4-way for the customers and procedures that ask for it, not as a default.
Yes. Both come with Luer lock ports and colour-coded handles, in the same pressure and sterility options. Tell us the configuration and we match it across both.
Send us your customer mix and we'll suggest the split.
We make both, in matching Luer lock, colour and pressure options. Tell Alex what your customers run and we'll suggest a 3-way to 4-way ratio, confirm the flow pattern, and come back with a sample, MOQ and FOB price, usually within a day.
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