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CDI Mainsail MR4-6 Furling System

Note: Some prices may reflect updates due to international tariffs. Learn the latest about tariffs

Tariff Updates

We are observing how the tariffs are behaving. Lots of our products are imported from Europe and some of the manufacturers are not providing heads up about price increases. We will do everything in our power to hold the best prices, but please consider that in these uncertain times we may be forced to increase the prices without previous notification.

We really appreciate your understanding and look forward to working with you.

What does this mean for you?

  • Some imported products may show a higher price than usual.
  • Prices may change as shipping rates adjust globally.
  • We are committed to providing the best possible pricing and transparency at all times.

How we’re handling it:

  • We only adjust prices when absolutely necessary.
  • We continuously monitor shipping rates and update pricing accordingly.
  • We’ll clearly notify you if a product is affected by tariffs.

Questions? Feel free to contact our team for any clarification or assistance.

Updated: April 2025

MSRP: $2,620.00
Was: $2,620.00
Now: $2,331.00
(You save $289.00 )
(1 review) Write a Review
SKU:
CDIMR4-6
Weight:
45.00 LBS
Shipping:
Calculated at Checkout.
Type:
Mainsail
Material:
PVC + Aluminum
Boat:
28 to 36 ft

Manufacturer part #: MR4-6

SystemDrum Diameter
Sailboats Size under 40' long
Mainsail Luffs up to 39'
Mainsails up to 400 Sq Ft area



Manufacturer part #: MR4-6

The Mainsail Reefing System delivers to the sailboat owner a reasonably priced mainsail reefing system that can be owner installed. The new system is based on the time proven design of the CDI Flexible Furler.

The Mainsail Reefing System by CDI eliminates flogging sails in the cockpit when reefing or furling the mainsail; can be reefed from the safety of the cockpit as easily as reefing the jib. As with a jib reefing product, the Mainsail Reefing system allows infinite size choices when reefing the mainsail to accommodate all wind and sea conditions. The Mainsail Reefing System by CDI is designed to be easily installed on existing boats, without costing more than the boat itself.



Manufacturer part #: MR4-6

CDI Flexible Furler FF4 Manual.pdf

Call us for technical support, customer service and product information (877) 240-VELA (8352)

1 Review Hide Reviews Show Reviews

  • 4
    best for not jamming

    Posted by chuck emigh on May 10th 2019

    this is the best idea yet for a mainsail furler that does not jam.
    the one piece plastic luff track comes all coiled up. great care needs to be taken when uncoiling it. we never did get one minor bend to come out.
    i hope cdi comes out with an aluminum modularized version. i would be the first in line to buy it. but this system is the only mainsail furler you don't have to worry about jamming as there is no shroud. since i don't race and do coastal crusing. it is perfect. the staylock was different than the manual but worked fine. CDI support was helpful but told us we needed professional riggers for the work on the top of the mast when we kept asking about the different staylock we got from the one in the manual. however they sent us picture of how both types would work and more pictures than what were in the manual. i was glad i hired a rigger for the work at the top of the mast.