Sizing Guide

Rocna or Vulcan 4

Anchor Weight Rocna fluke area Vulcan fluke area Rec. G40 chain Approx weight Typical WLL Typical break
4 kg
9 lb
71 in2 65 in2 6 mm
1/4"
0.80 kg/m
84 lb/100'
400 kgf
2600 lb
1630 kgf
7800 lb
Shackle pin size Typical high load body diameter
< 8 mm < 7 mm

Multi-hulls have higher windage than mono-hulls, and therefore we recommend a larger size anchor. Use the guide as instructed, then select the model one size larger.


Rocna or Vulcan 6

Anchor Weight Rocna fluke area Vulcan fluke area Rec. G40 chain Approx weight Typical WLL Typical break
6 kg

13 lb
91 in2 87 in2 6 mm
1/4"
0.80 kg/m
84 lb/100'
400 kgf
2600 lb
1630 kgf
7800 lb
Shackle pin size Typical high load body diameter
< 8 mm < 7 mm

Fyran Pursuit 600 GT

Fyran Pursuit 600 GT

Multi-hulls have higher windage than mono-hulls, and therefore we recommend a larger size anchor. Use the guide as instructed, then select the model one size larger.


Vulcan 9

Anchor Weight Rocna fluke area Vulcan fluke area Rec. G40 chain
9 kg
20 lb
- 113 in2 7 mm
1/4"
Shackle pin size Typical high load body diameter
< 9 mm < 8 mm

Mustang 2800 III

Bayliner 2750

Bayliner 28

Ciera 2855

Catalina 30

Mustang 2800 III

Multi-hulls have higher windage than mono-hulls, and therefore we recommend a larger size anchor. Use the guide as instructed, then select the model one size larger.


Rocna 10

Anchor Weight Rocna fluke area Vulcan fluke area Rec. G40 chain Approx weight Typical WLL Typical break
10 kg
22 lb
123 in2 - 7 mm
1/4"
1.00 kg/m
84 lb/100'
630 kgf
2600 lb
2548 kgf
7800 lb
Shackle pin size Typical high load body diameter
< 9 mm < 8 mm

Elan 31

Beneteau 281

Beneteau First 31.7

Catalina 34

Compass 28

Elan 31

Hunter H260

MacGregor 26M

Mirage 33

Multi-hulls have higher windage than mono-hulls, and therefore we recommend a larger size anchor. Use the guide as instructed, then select the model one size larger.


Vulcan 12

Anchor Weight Rocna fluke area Vulcan fluke area Rec. G40 chain
12 kg
27 lb
- 136 in2 8 mm
5/16"
Shackle pin size Typical high load body diameter
< 10 mm < 9 mm

Back Cove 33


Back Cove 33

Multi-hulls have higher windage than mono-hulls, and therefore we recommend a larger size anchor. Use the guide as instructed, then select the model one size larger.


Rocna or Vulcan 15

Anchor Weight Rocna fluke area Vulcan fluke area Rec. G40 chain Approx weight Typical WLL Typical break
15 kg
33 lb
160 in2 158 in2 8 mm
5/16"
1.40 kg/m
120 lb/100'
800 kgf
3900 lb
4030 kgf
11700 lb
Shackle pin size Typical high load body diameter
< 10 mm < 9 mm

Superior 1050

Bavaria 30

Bavaria 38 Cruiser

Bavaria 34 Cruiser

Beneteau Oceanis 361

C&C 35 Mk 1

Dufour 35

Dufour 35 Classic

Gemini 105MC

Genesis 335

Hanse 371

Jeanneau Sun Odyssey 35

Nimbus Nova 31 S HT

Kelsall 39 trimaran

Pacific Seacraft 34

Pro-Line 35 Express

Pursuit 3070 Offshore

Superior 1050

Vancouver 28

Multi-hulls have higher windage than mono-hulls, and therefore we recommend a larger size anchor. Use the guide as instructed, then select the model one size larger.


Rocna or Vulcan 20

Anchor Weight Rocna fluke area Vulcan fluke area Rec. G40 chain Approx weight Typical WLL Typical break
20 kg

44 lb
177 in2 192 in2 9 mm
5/16"
1.80 kg/m
120 lb/100'
1000 kgf
3900 lb
4077 kgf
11700 lb
Shackle pin size Typical high load body diameter
< 12 mm < 11 mm

Southerly 32

Allied Seawind 30

Back Cove 37

Bavaria 39 Cruiser

Beneteau Oceanis 43

Bluewater 400

Catalina 380

Fountaine Pajot Mahe 36

Jeanneau Sun Odyssey 42i

Lagoon 380

Maverick 400

Najad 380

Nauticat 39

George Buehler Juna Junosdautter

Riviera M370

Southerly 32

Multi-hulls have higher windage than mono-hulls, and therefore we recommend a larger size anchor. Use the guide as instructed, then select the model one size larger.


Rocna or Vulcan 25

Anchor Weight Rocna fluke area Vulcan fluke area Rec. G40 chain Approx weight Typical WLL Typical break
25 kg
55 lb
219 in2 223 in2 10 mm
3/8"
2.35 kg/m
176 lb/100'
1250 kgf
5400 lb
5096 kgf
16200 lb
Shackle pin size Typical high load body diameter
< 15 mm < 13 mm

Walkabout 43

Alliage 41

Bavaria 42 Cruiser

Catalina 42 MK II

Colvic Watson 34'6"

Fountaine Pajot Lavezzi 40

Grand Soleil 45

Hallberg-Rassy 40

Hanse 430e

Jeanneau Sun Odyssey 37

Jeanneau Sun Odyssey 45

Lagoon 400

Leopard 40

Manta 42

Kalik 44

Rival 36

Tayana 37

Walkabout 43

Warwick 14M

Westerly Sealord 39

Multi-hulls have higher windage than mono-hulls, and therefore we recommend a larger size anchor. Use the guide as instructed, then select the model one size larger.


Rocna or Vulcan 33

Anchor Weight Rocna fluke area Vulcan fluke area Rec. G40 chain Approx weight Typical WLL Typical break
33 kg
73 lb
263 in2 268 in2 10 mm
3/8"
2.35 kg/m
176 lb/100'
1250 kgf
5400 lb
5096 kgf
16200 lb
Shackle pin size Typical high load body diameter
< 15 mm < 13 mm

Wauquiez Centurion 49

Callisto 385

Fountaine Pajot Bahia 46

Ganley S130

Garcia Exploration 45

Hallberg-Rassy 46

Hanse 470e

Hanse 540e

Lagoon 39

Lagoon 421

Langedrag 441

Peterson 44

Wauquiez Centurion 49

Multi-hulls have higher windage than mono-hulls, and therefore we recommend a larger size anchor. Use the guide as instructed, then select the model one size larger.


Rocna or Vulcan 40

Anchor Weight Rocna fluke area Vulcan fluke area Rec. G40 chain Approx weight Typical WLL Typical break
40 kg
88 lb
301 in2 305 in2 11 mm
7/16"
2.60 kg/m
230 lb/100'
1600 kgf
7200 lb
6422 kgf
21600 lb
Shackle pin size Typical high load body diameter
< 15 mm < 13 mm

Solo 43

Grand Banks 46

Hatteras 50

Liberty 458

Maple Leaf 48

Post 50 Sportfisherman

Solo 43

Multi-hulls have higher windage than mono-hulls, and therefore we recommend a larger size anchor. Use the guide as instructed, then select the model one size larger.


Rocna or Vulcan 55

Anchor Weight Rocna fluke area Vulcan fluke area Rec. G40 chain Approx weight Typical WLL Typical break
55 kg
121 lb
357 in2 377 in2 12 mm
7/16"
3.30 kg/m
230 lb/100'
2120 kgf
7200 lb
8480 kgf
21600 lb
Shackle pin size Typical high load body diameter
< 16 mm < 13.5 mm

Tayana 55

Asko Marine Custom 19m

Catana 521

Chuck Paine Lyman Morse 54

Hallberg-Rassy 54

Moody 54

Ocean Alexander 58

Oyster 56

Tayana 52

Tayana 55

Multi-hulls have higher windage than mono-hulls, and therefore we recommend a larger size anchor. Use the guide as instructed, then select the model one size larger.


Rocna 70

Anchor Weight Rocna fluke area Vulcan fluke area Rec. G40 chain Approx weight Typical WLL Typical break
70 kg
154 lb
417 in2 - 14 mm
1/2"
3.90 kg/m
300 lb/100'
2500 kgf
9200 lb
10000 kgf
27600 lb
Shackle pin size Typical high load body diameter
< 18 mm < 16 mm

Herbert Woods Custom 20m

Herbert Woods Custom 20m

Multi-hulls have higher windage than mono-hulls, and therefore we recommend a larger size anchor. Use the guide as instructed, then select the model one size larger.


Rocna 110

Anchor Weight Rocna fluke area Vulcan fluke area Rec. G40 chain Approx weight Typical WLL Typical break
110 kg
243 lb
516 in2 - 16 mm
5/8"
6.10 kg/m
400 lb/100'
4100 kgf
13000 lb
16400 kgf
39000 lb
Shackle pin size Typical high load body diameter
< 22 mm < 19 mm

Dashew FPB 83

Dashew FPB 83

Multi-hulls have higher windage than mono-hulls, and therefore we recommend a larger size anchor. Use the guide as instructed, then select the model one size larger.


(*) Classification Rules sizing

Rocna anchors from size 110 kg (243 lb) and above may be sized based on classification society Rules for Ships for SHHP anchors. Modern rules permit a mass 33% lighter than HHP types, or 50% lighter than “standard stockless” types. Anchor sizing is based on a vessel’s separately calculated Equipment Number (EN). For more information, please consult the Rocna Knowledge Base articles on our sizing recommendations and Classification and Certification.

  Equipment Number (EN) range (applies to Lloyd's, RINA)
  50-70 70-110 110-130 130-175 >175
ROCNA MODEL 110 150 200 275 Please enquire
Anchor weight 110 kg 150 kg 200 kg 275 kg
243 lb 331 lb 441 lb 601 lb
Fluke surface area 2300 cm2 4470 cm2 5560 cm2 6510 cm2