Red
Horizontal
2 flashes in a group
These marks are used to show the location of a small hazard, which must have navigable water all around it.
| Feature | Colour | |
|
|---|---|---|---|
| Buoyage shape | Buoy or a pillar |
||
| Buoyage colour | Black Red Horizontal |
||
| Topmark shape | 2 balls | ||
| Topmark colour | Black | ||
| Light rhythm | Q (2) or VQ (2), 2 flashes in a group |
||
| Light colour | White |
These show the middle of the main channel, and encourage vessels to keep separated into lanes.
| Feature | Colour |     |
 |
|---|---|---|---|
| Buoyage shape | Buoy or a pillar | ||
| Buoyage colour | Red White Vertical |
||
| Topmark shape | 1 ball | ||
| Topmark colour | Red | ||
| Light rhythm | Isophase, occulting, L.Fl.10s or Mo(A) |
||
| Light colour | White |
These show areas of special use such as
| Feature | Colour |  |
 |
|---|---|---|---|
| Buoyage shape | Any | ||
| Buoyage colour | Yellow | ||
| Topmark shape | Cross | ||
| Topmark colour | Yellow | ||
| Light rhythm | Any that can not be confused with a nearby white light |
||
| Light colour | Yellow |
Click here to see how these buoys are used.