The Short Answer
WI07 through WI13 are variants across two Daytech window intercom lines: a single-way microphone-and-speaker series for one-directional counters, and a dual-way full-duplex system for two-sided conversations. The model number tells you the housing and mic configuration, not a generation upgrade, so picking between them comes down to your counter type, not chasing the highest number.
A quick scroll through a hardware supplier's catalog turns up WI07, WI08, WI09, WI11, WI12, and WI13, all labeled window intercom, all similarly priced, and all looking almost identical in a thumbnail photo. It's the kind of listing that makes a buyer default to whichever one comes up first, which sometimes means overpaying for a feature they didn't need or, worse, buying a single-way mic for a counter that really needed two-way conversation. Before ordering, it's worth pulling up both the Anti-Interference Window Intercom Microphone line and the Dual-Way Counter Intercom System side by side, because the real decision point is between those two families, not between individual model numbers within one family.
The Two Families, Not Six Products
Daytech's WI-series sits across two functional categories. The single-way microphone-and-speaker units are built for a counter where one side mostly listens and speaks, such as a customer talking to staff behind glass; audio flows from a mic on the customer side to a speaker on the staff side, with the staff member typically speaking back at normal volume since they're not behind the same acoustic barrier problem. The dual-way system, by contrast, puts a full microphone-and-speaker pair on both sides, letting both people talk and be heard simultaneously, closer to how a telephone call works.
Spec Comparison at a Glance
| Model Range | Audio Direction | Best For | Typical Price Range (PHP) |
|---|---|---|---|
| WI07, WI08, WI09 | Single-way (customer to staff, staff speaks back naturally) | Pharmacy, small retail, single-window government counters | 1,449 to 1,599 |
| WI11, WI12 | Single-way, compact housing variants | Tight counter spaces, kiosk windows | 1,449 to 1,499 |
| WI13 and dual-way system units | Full duplex, both sides | Bank teller counters, guardhouses, high-security glass | 1,170 to 1,380 (dual-way line) |
Price is not a reliable signal of capability here. The dual-way system line actually lists lower on some variants than the single-way anti-interference line, because the pricing reflects component cost and housing, not a strict better-to-worse ladder. This is the single most common mistake in ordering: assuming a higher model number or a higher price means a more capable unit, when the real fork in the road is single-way versus dual-way.
Where the Comparison Breaks Down
Daytech doesn't publish a detailed public changelog between every WI model, so some of this mapping comes from cross-referencing catalog listings and installer feedback rather than a single official spec sheet. If your counter has an unusual requirement, extreme outdoor exposure, a very thick security glass panel, or a need to daisy-chain multiple windows to one control unit, it's worth confirming the exact current specification with us directly rather than relying on the model number alone, since suppliers do occasionally revise a unit's internals without changing its name.
How to Actually Choose
Start with the question a spec sheet can't answer for you: does staff need to just be heard clearly, or does the counter need a real two-way conversation with both sides talking naturally at the same time? A single pharmacy or registrar window usually only needs the former, at the lower end of the single-way line. A bank teller counter, a guardhouse, or anywhere staff need to ask follow-up questions mid-conversation should default to the dual-way system instead. From there, compact housing variants like the WI11 and WI12 make sense only if counter space is genuinely tight, since they don't add capability, only a smaller footprint. Questions about matching a specific counter to a specific model can go through our contact page before ordering.
