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Description
Ronstan Orbit Series 55 Single Fiddle Block w/ Becket & Swivel HeadProduct Description Ronstan Orbit Series 55 Single Fiddle Block w Becket & Swivel Head Features Automatic and Manual ratchet in one block Up to 20: 1 holding power Smooth easing of sheets High performance cleating Sheave 2 5 32 + 1 3 8 in. (55 + 35mm) Max. Rope 10 in. (3 8mm) Max. Cable in (mm) Pin in. (mm) M. W. L. 550 lb. (250 kg) B. L. 1650 lb. (750 kg) Weight 3. 9 oz. (112 g) Fiddle sheave has a high load full contact bearing (ie. not ball
Product Description
Ronstan Orbit Series 55 Single Fiddle Block w/ Becket & Swivel Head
Features
Automatic and Manual ratchet in one block
Up to 20:1 holding power
Smooth easing of sheets
High performance cleating
Sheave Ø - 2 5/32 + 1 3/8 in. (55 + 35mm)
Max. Rope Ø - 10 in. (3/8mm)
Max. Cable Ø - in (mm)
Pin Ø - in. (mm)
M.W.L. - 550 lb. (250 kg)
B. L. - 1650 lb. (750 kg)
Weight - 3.9 oz. (112 g)
Fiddle sheave has a high load full contact bearing (ie. not ball bearing). Main sheave has two-stage, ball bearing
Product Information
Automatic ratchet block
Now you can enjoy the flexibility of setting up your ratchet blocks to suit yourself. Ronstan is the only company that offers a ratchet block with both auto and manual engagement modes*. In the auto mode of the ratchet mechanism engages when load is applied, but switches off when it's released. This lets the sheet run out smoothly and freely-great for rapid easing of the sheet and for gybing asymmetric spinnakers. In manual mode, the ratchet mechanism can be switched on or off as required. This is the preferred mainsheet set-up for may top sailors. Try the block in both modes and see which you prefer - you really can't go wrong.
Selected Series 55 models.
Awesome ratchet block holding power
Quite simply, Ronstan Ratchet Orbit Blocks™ have the highest holding power available. The sophisticated NC-machined sheave features Generation 2 of our patented sheave cross-hole geometry. Its holding power is up to 21:1, almost double that of our nearest competitior. The unique sheave design has 12 gripping faces which directly resist loaded line movement. Traditional designes have only 8 faces with an angled resistance to line movement. Our Generation 2 design has straight resistance faces which both distribute the load and minimise rope wear. These faces are offset from the radial line, to draw the rope down into the gripping area when under load.
Materials
Sheave: Hard anodized Aluminum
Ball Bearings: High compression strength carbon black Acetal
Frame/Cheeks: Toughened, glass fibre reinforced Nylon
Rope Link: UV stabilised, multi-strand impregnated SK75 Dyneema®
Features
Sheave Ø - 2 5/32 + 1 3/8 in. (55 + 35mm)
Max. Rope Ø - 10 in. (3/8mm)
Max. Cable Ø - in (mm)
Pin Ø - in. (mm)
M.W.L. - 550 lb. (250 kg)
B. L. - 1650 lb. (750 kg)
Weight - 3.9 oz. (112 g)
Product Information
Automatic ratchet block
Now you can enjoy the flexibility of setting up your ratchet blocks to suit yourself. Ronstan is the only company that offers a ratchet block with both auto and manual engagement modes*. In the auto mode of the ratchet mechanism engages when load is applied, but switches off when it's released. This lets the sheet run out smoothly and freely-great for rapid easing of the sheet and for gybing asymmetric spinnakers. In manual mode, the ratchet mechanism can be switched on or off as required. This is the preferred mainsheet set-up for may top sailors. Try the block in both modes and see which you prefer - you really can't go wrong.
Awesome ratchet block holding power
Quite simply, Ronstan Ratchet Orbit Blocks™ have the highest holding power available. The sophisticated NC-machined sheave features Generation 2 of our patented sheave cross-hole geometry. Its holding power is up to 21:1, almost double that of our nearest competitior. The unique sheave design has 12 gripping faces which directly resist loaded line movement. Traditional designes have only 8 faces with an angled resistance to line movement. Our Generation 2 design has straight resistance faces which both distribute the load and minimise rope wear. These faces are offset from the radial line, to draw the rope down into the gripping area when under load.
Materials
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.7 ★★★★★
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Product Reviews
★★★★★ 5
Better running mower
Seems to work fine and runs great
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 15, 2026
★★★★★ 4
Perfect Spark Plug
Perfect match for my lawnmower. Worked as soon as I placed it on. Great product. Thank you Amazon for the product. Fast, correct product, and affordable
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Reviewed in the United States on April 29, 2026
★★★★★ 5
Cost-effective alternative that works well..
I used these spark plugs on my 2018 Cub Cadet XT2 riding mower as part of the spring preparation. The spark plugs were well packed and arrive in great shape and at the appropriate gap. No issues with starting or operating the mower. These Harbot plugs turned out to be a great cost-effective option for me.
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Reviewed in the United States on April 4, 2026
★★★★★ 5
They work great.
The spark plugs are an exact replacement for my riding mower.
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Reviewed in the United States on May 10, 2026
★★★★★ 5
Good spark
Plugs work well. Mower seams smoother
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Reviewed in the United States on April 30, 2026