Harken 3237 75 mm Aluminum Double Footblock Lockoff
Harken 3237 75 mm Aluminum Double Footblock Lockoff additional 1Harken 3237 75 mm Aluminum Double Footblock Lockoff additional 2Harken 3237 75 mm Aluminum Double Footblock Lockoff additional 3
Free UK Delivery

£755.23 inc VAT


Item has been added to your cart

Lead Time: Please allow 10-14 days for delivery
  • Free Delivery
    on all orders over £100
  • Not Quite Right?
    14 day money back guarantee
  • Worldwide Delivery
    UPS secure & signed for

This 75 mm Aluminum Double Footblock Lockoff from Harken has been specifically made to take on the high loads required of running rigging.

Strong and lightweight, this boat block features Torlon roller bearings, housed in a center cage for even more added protection.

Part of the Harken range of Black Magic Airblocks, this device features a newly redesigned look, with the same performance-heavy design of previous boat blocks.

The rollers stay parallel for low-friction efficiency, whilst the sculpted hardcoat-anodized aluminum sideplates help protect sideload ball bearings.

  • Dissimilar metals are isolated to minimize corrosion
  • Blocks are easily disassembled with a single hex wrench
  • Use footblocks to redirect lines on the deck. Footblocks with lockoffs temporarily secure sheets
  • Either metric or imperial flathead fasteners may be used for mounting and are not exposed


  • Height (mm):57
  • Height (in):2 1/4
  • Fasteners (mm):8 FH
  • Fasteners (in):5/16 FH
  • Maximum Line Ø (mm):14
  • Maximum Line Ø (in):9/16
  • Length (mm):111
  • Length (in):4 3/8
  • Weight (g):574
  • Weight (oz):20.24
  • A (mm):10
  • A (in):3/8
  • B (mm):29
  • B (in):1 1/8
  • C (mm):71
  • C (in):2 13/16
  • Sheave Ø (mm):75
  • Sheave Ø (in):2 15/16
  • Maximum Working Load (kg):1572
  • D (mm):21
  • Maximum Working Load (lb):3465
  • E (mm):76
  • F (mm):110
  • G (mm):16
  • Breaking Load (kg):3143
  • D (in):13/16

Product Code:3237


Mainland UK Delivery

Delivery OptionDelivery TimeTrackedSigned ForCost
Standard Delivery (Orders Under £100)2-3 Working DaysNoNo4.00
All Standard Orders Over £1002-3 Working DaysYesYesFREE

Delivery Surcharges: Liquids, Paint & Gas

(Flares UK Mainland Only)

1-2 Working DaysYesYes£3.50
Delivery Surcharges: Flares (UK Mainland Only)1-2 Working DaysYesYes£35

Non-Mainland UK and International Delivery

For European and International Deliveries please contact us first for a quote - call on 01326 375482 or email sales@mylorchandlery.co.uk 

How quickly will my order arrive?

Our aim is to dispatch all orders placed before 12 noon on the same day. Any orders placed after that time will be dispatched on the next available working day.

We will send you a notification email when your order has been dispatched. The time your order takes to arrive will depend on the delivery option you have choosen.

Whilst we try our best to dispatch every order following the above guidelines, during extremely busy periods, dispatch times may increase by up to one day.

How can I track the status of my order?

You will receive an email to confirm we have received your order and that your payment has been accepted. You will also receive an email when your order has been dispatched.

In your dispatch confirmation email we will include any relevant tracking numbers, allowing you to track your parcel on either the DHL, Royal Mail & DPD website. However, if the order is under £20 it will be sent standard second-class post with no tracking. You will only receive a tracking number if you have chosen a tracked delivery option for your order.



All orders are thoroughly checked before leaving our premises. On receipt of your order we request that you check the items as soon as possible. If you are unhappy with your order for any reason, please contact us immediately on 01326 375 482 or support@mylorchandlery.co.uk. Please have your order number to hand when you contact us as it will allow us to find your order quickly.

If you are unsatisfied with your order in any way, please return it to us within 14 days of delivery for a refund or exchange. The item must be unused, be in its original packaging and be suitable for re-sale. Items bought in the sale are non-returnable and non-refundable. Postage costs for returning items to us can only be refunded if the item is faulty or damaged.

We recommend that you send your order back to us by obtaining a ‘proof of posting’ (free at all Post Offices) or alternatively using a tracked delivery service. Please note we cannot be held responsible for any parcel lost during transit to us. 

Our return address is:

Web Returns
Mylor Chandlery Ltd 
Mylor Yacht Harbour
TR11 5UF

Once your item has been returned, we will inspect it and take the necessary action as soon as possible.

Faulty/Damaged Goods

If any item you receive arrives damaged, please contact us as soon as possible on 01326 375 482 or by email support@mylorchandlery.co.uk.  We will then advise you on the best course of action. 

In most cases we will ask you to return the item to us for an exchange or refund. Unfortunately we can only refund your postage costs when you return an item to us that is faulty.

Please do not return a damaged order to us without contacting us first.