These dual purpose systems offer sailors the option of either speed or power. They are used for mainsheets on small to medium-sized offshore boats where power is required for effective heavy-air trimming upwind, but speed is crucial for off-wind trimming and mark roundings.
Typical boat length:
Small Boat: 22' - 28' (6.7 - 8.5 m)
Midrange: 29' - 34' (8.8 - 10.4 m)
Big Boat: 35' - 42' (10.7 - 12.8 m)
2:1/4:1 Swivel Base
This system is often found on boats like J/24s where a center-mounted swivel base is desired.

Diagram Ref. |
Description |
Small Boat Part No. |
Midrange Part No. |
Big Boat Part No. |
A |
Double |
2602 |
|
|
B |
Single |
2600 |
|
|
C |
Double |
2634 |
|
|
D |
Cam base |
402 |
|
|
|
3:1/6:1
This 3:1/6:1 two-speed system is used on boats end-boom sheeting and mainsails up to 22.3 m² (240 ft²).

Diagram Ref. |
Description |
Small Boat Part No. |
Midrange Part No. |
Big Boat Part No. |
A |
Cross Block |
400
|
400 |
|
B |
Fiddle |
401 |
401 |
|
|
3:1/6:1 Swivel Base
This 3:1/6:1 system allows the mainsheet trimmer to be positioned anywhere on the boat. A great setup for sportboats.

Diagram Ref. |
Description |
Small Boat Part No. |
Midrange Part No. |
Big Boat Part No. |
A |
Single |
2600
|
2600 |
|
B |
Double |
2602 |
2602 |
|
C |
Double | 2634 |
2634 |
|
D |
Cam base |
402 |
402 |
|
|
4:1/8:1 Swivel Base
Similar to the 3:1/6:1 swivel base system, but uses a 4:1/8:1 tackle for more power.

Diagram Ref. |
Description |
Small Boat Part No. |
Midrange Part No. |
Big Boat Part No. |
A |
Double |
2602 |
2602 |
|
B |
Cross block |
400 |
400 |
|
C |
Double | 2634 |
2634 |
|
D |
Cam base |
402 |
402 |
|
|
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