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Over 50 years of Trusted Marine Service

Lewmar 60mm Synchro Block – Double, Black, 5/16”–3/8” Line

Original price $145.41 - Original price $145.41
Original price
$145.41
$145.41 - $145.41
Current price $145.41
Item locally warehoused

Free returns on all eligible orders

You have 30 days to request a return. All sale items are final sale.

Two-Sheave Efficiency for Mid-Size Running Rigging

The Lewmar 60mm Synchro Double Block delivers smooth, low-friction performance across two sheaves in a compact, lightweight package. Its high-density, free-spin plain bearing and self-aligning swivel head minimize friction under load, keeping lines running cleanly whether you’re sheeting in, easing out, or redirecting a control line. The patented shackle post lock makes attachment and removal fast and secure without tools.

Stainless steel straps and glass-fibre reinforced cheeks provide the durability performance sailors demand, while the matched sheave, bearing, pin, and line sizing ensures optimum efficiency across the 5/16”–3/8” line range.

Compatible Applications

  • Two-part sheet and halyard systems
  • Mainsheet and traveler systems requiring two-line leads
  • Running rigging on performance sailboats
  • Multi-part purchase systems (working end, paired with a becket block)
  • Line sizes: 5/16” to 3/8” (8–10mm)
  • Block size: 60mm sheave diameter

Product Details

  • Configuration: Double sheave
  • Sheave diameter: 60mm
  • Line range: 5/16”–3/8” (8–10mm)
  • Color: Black
  • Bearing: High-density free-spin plain bearing
  • Head: Self-aligning swivel
  • Construction: Stainless steel straps, glass-fibre reinforced cheeks
  • Attachment: Patented shackle post lock
  • SKU: 239-29926002BK

Parts Desk Insights

Best Use Case: The plain double block is the working end of a purchase system — pair it with a Double with Becket or Single with Becket to build a 3:1 or 4:1 mainsheet or vang system. It’s also useful anywhere you need to run two lines through a single attachment point without the added weight of a cam or becket. The 60mm size is well-suited to mid-size performance sailboats running 5/16”–3/8” line.

Other 60mm Synchro Blocks

Other Synchro Block Sizes

Pair It With

Shipping information

In-stock and OEM parts: ship same or next business day.

Locally warehoused items: ship within 1-3 business days.

Special-order items: timeline confirmed after order.

Returns & warranty

Returns & Satisfaction Guarantee

We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.

If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.

To qualify for a return:


  • Item must be in new, unused condition

  • Product must be in its original packaging

  • All parts, components, hardware, manuals, and accessories must be included

  • Packaging must be undamaged and suitable for resale

Important:

Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.

We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.

For return authorization, please contact our support team before shipping anything back.

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