Single Blocks | West Coast Sailing - Sailboat Blocks & Hardware

Ronstan 15 mm Utility Single Block

$11.98

Ronstan
Ronstan 15 mm Utility Single Swivel Block

$20.98

Ronstan
Ronstan 15 mm Utility Single Block with Becket

$14.18

Ronstan
Ronstan 15 mm Utility Single Stand Up Block

$18.55

Ronstan
Harken 16 mm Single Block H404

$16.95

Harken
Harken 16 mm Single Block w/ Swivel H417

$29.95

Harken
Harken 16 mm Single Block w/Becket H405

$18.95

Harken
Harken 16mm Single Forkhead Block H376

$22.95

Harken
Harken T2 18 mm Narrow Head Block H2161

$23.95

Harken
Ronstan 20 mm Single Block

$11.98

Ronstan
Ronstan 20 mm Orbit Block Single

$13.98

Ronstan
Ronstan 20 mm Swivel Block

$20.98

Ronstan

Single Blocks

These blocks have a single sheave for one turning point and are common in many sailboat rigging applications.

Sailing Hardware Experts
West Coast Sailing is your go to source for sailing hardware and blocks for your sailboat. We offer and stock a huge range of components from Harken, Ronstan, and more in a range of sizes and configurations to meet your rigging needs. Chat with our staff of sailors by emailing us at info@westcoastsailing.net or calling/texting to 503-285-5536.

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Dinghy / Small Boat Recreational	4mm / 5mm Robline Sirius 500
Dinghy / Small Boat Performance	2mm / 3mm / 4mm / 5mm Robline Dinghy Control 4mm / 5mm Marlow Excel Racing
Keelboat / Cruising Recreational	6mm Marlow DoubleBraid
Keelboat / Cruising Performance	6mm Robline Dinghy Control Line

Dinghy / Small Boat Recreational	5mm Robline Sirius 500 6mm Marlow Pre Stretch
Dinghy / Small Boat Performance	5mm Robline Dinghy Control 4mm / 6mm Alpha SSR
Keelboat / Cruising Recreational	6mm Robline Orion 300 6mm / 8mm Marlow DoubleBraid
Keelboat / Cruising Performance	6mm / 8mm / 10 mm Robline Admiral 5000

Dinghy / Small Boat Recreational	8mm Robline Orion 500 6-8mm New England Ropes Bzzz 6mm-12mm Marlow DoubleBraid
Dinghy / Small Boat Performance	6mm-7mm Rooster Polilite 6mm-8mm Dinghy Sheet XL
Keelboat / Cruising Recreational	6mm-12mm Marlow DoubleBraid 9mm Top Cruiser Kmix 10mm-11mm Robline Orion 300
Keelboat / Cruising Performance	6mm-8mm Samson Ultra-Lite 5.5mm-9mm Coppa 5000

Application	Boat Length 10 - 18 Feet	Boat Length 18 - 24 Feet	Boat Length 24 - 32 Feet	Boat Length 32 - 38 Feet	Boat Length 38 - 45 Feet	Boat Length 45 - 52 Feet
Main Halyard	6mm / 1/4 in	6mm / 1/4 in	8mm / 5/16 in	8mm / 5/16 in	9mm / 3/8 in	11mm / 7/16 in
Jib/Genoa Halyard	6mm / 1/4 in	6mm / 1/4 in	8mm / 5/16 in	8mm / 5/16 in	9mm / 3/8 in	11mm / 7/16 in
Spinnaker Halyard	6mm / 1/4 in	6mm / 1/4 in	8mm / 5/16 in	9mm / 3/8 in	9mm / 3/8 in	11mm / 7/16 in
Topping Lift	6mm / 1/4 in	6mm / 1/4 in	8mm / 5/16 in	9mm / 3/8 in	9mm / 3/8 in	11mm / 7/16 in
Mainsheet	8mm / 5/16 in	9mm / 3/8 in	9mm / 3/8 in	9mm / 3/8 in	11mm / 7/16 in	12mm / 1/2 in
Jib/Genoa Sheet	6mm / 1/4 in	8mm / 5/16 in	9mm / 3/8 in	9mm / 3/8 in	11mm / 7/16 in	12mm / 1/2 in
Spinnaker Sheet	6mm / 1/4 in	8mm / 5/16 in	8mm / 5/16 in	8mm / 5/16 in	9mm / 3/8 in	9mm / 3/8 in
Tack Line	5mm / 3/16 in	6mm / 1/4 in	9mm / 3/8 in	9mm / 3/8 in	9mm / 3/8 in	11mm / 7/16 in

MM to Inch Conversion Chart	1mm = 3/64 inch	2mm = 5/64 inch	3mm = 1/8 inch	4mm = 5/32 inch	5mm = 3/16 inch	6mm = 1/4 inch
MM to Inch Conversion Chart	7mm = 9/32 inch	8mm = 5/16 inch	9mm = 3/8 inch	10mm = 25/64 inch	11mm = 7/16 inch	12mm = 1/2 inch