To plan ultrasonic repeller coverage area, start with one unit per enclosed room, then check whether that room is larger than the rated coverage of the model you stock. Ultrasound does not pass through walls or closed doors, so a three-room shop needs at least three units even if its total floor area is small, and a large open warehouse needs several units spread across zones.

Below is how we explain it to importers, retailers and online sellers who want to give their customers a clear "how many do I need" answer on the box, listing or shelf talker.

How far does an ultrasonic repeller reach?

Every coverage figure on our product pages is measured for an open, unobstructed space. Real rooms are rarely like that. Ultrasound travels in a fairly straight line and is absorbed or blocked by walls, doors, sofas, curtains, stacked cartons and shelving. That is why our specifications say "in an open room" or "in an open space" next to every number.

Here is the rated coverage of current plug-in and floor models, taken from their detail pages:

For SDH-045 and SDH-046 the user manual is more conservative than the open-space figure: it recommends one unit for every 30 m², with several units working together in large spaces. We suggest you print the planning figure from the manual on your packaging or listing, not only the maximum open-space number, so end users set realistic expectations.

How many ultrasonic repellers do I need for one room?

For a normal home room, office or stockroom the answer is usually one. Use this quick check:

  1. Is the room enclosed by walls and a door? If yes, it counts as its own zone.
  2. Is the floor area within the planning figure for the model? If yes, one unit.
  3. Is the room L-shaped, divided by a half wall, or full of tall furniture? Treat each section with a direct line of sight as its own zone.

Placement matters as much as quantity. Most of our plug-in models should sit low on the wall, roughly 15–50 cm above the floor depending on the model, with nothing in front of the speaker. A unit plugged in behind a sofa or under a desk covers far less than its rated area.

How many repellers for a warehouse?

Warehouses look like one big open room, but racking and pallets break the space into corridors. A simple method buyers use for planning:

  1. Measure each aisle or open zone separately, not the whole building.
  2. Divide each zone by the coverage of the model you plan to use, and round up.
  3. Add units for enclosed areas: offices, loading bays with doors, plant rooms.
  4. Follow the placement height in each model's manual and keep a clear path in front of the speaker along the aisle.

Floor-standing, higher-output models such as SDH-041 suit long open aisles and loading areas, because a single unit covers more floor. Plug-in models such as SDH-047 or SDH-046 suit offices and smaller rooms off the warehouse floor. Note that SDH-058 has a powerful cycle mode with an audible 200 Hz segment that is meant for unoccupied areas like warehouses after hours.

How many repellers for a store or restaurant?

A shop or restaurant usually has several enclosed zones even when the sales floor is small: the sales floor, a stockroom, a staff room, a kitchen or back area, and sometimes a basement. Count each one. A 90 m² shop with a stockroom and a staff toilet is three zones, not one.

For customer-facing areas, a practical approach is to use plug-in models in their everyday modes, and keep stronger cycle modes for back rooms and unoccupied hours.

What this means for your order

If you sell to end users, quantity planning is also a merchandising question. One option is to offer multi-packs for homes with several rooms, and a separate higher-output model for garages and storage areas. A few factory details that help when you plan:

  • Each repeller model is normally kept at about 3,000 units in stock, in neutral packaging with an English manual, with no minimum order for stock items.
  • Plug types are US, EU or UK, confirmed per order.
  • SDH-047 (EU) is packed 4 units per box, 45 boxes (180 units) per carton, carton size 50 × 38.5 × 46 cm, which makes mixed multi-pack planning easy.
  • For your own brand, logo and manual printing start at 500 units per model; housing colour and printed colour box start at 2,000 units per model. Production takes about 12 days after the sample and artwork are approved.
  • Our repellers carry CE and FCC, and are made in an EPA-registered establishment, Est. No. 97987-CHN-1. New models get a 24-hour aging test on the first batch, and repeat orders are sampled every batch; you can read more in how we test repellers, hand warmers and heated belts.

If you are still deciding between plug-in, car and solar formats, see our guide to choosing ultrasonic repellers: plug-in, car or solar.

Quick answers buyers ask

  • Does one unit cover a whole house? No. Ultrasound does not pass through walls, so plan one unit per room.
  • Can I use two units in one large room? Yes. For rooms larger than the planning figure, or rooms with tall furniture, several units working together give more even coverage.
  • Should coverage figures go on my listing? Use the open-space figure with the words "open, unobstructed room", and add the one-unit-per-room note so customers order the right quantity.

Request a quote or read our OEM and wholesale terms.