![Ronstan Series 40 All Purpose Block - Double Block - Full Swivel Head [RF41200]](https://www.bestmarinebattery.com/wp-content/uploads/2026/08/ronstan-series-40-all-purpose-block-double-block-full-swivel-head-rf41200.webp)
Description
Series 40 All Purpose Block – Double Block – Full Swivel Head
All purpose (AP) blocks are a great all around solution. Self-lubricating Acetal polymer sheaves running on polished stainless steel races perform equally well with dynamic loads and high static loads. For durability and a long service life, these blocks are the right choice for sheets, halyards and control line applications for cruising and racing. Head swivels freely.
Features:
- Exceptionally high working loads
- Low maintenance, long service life
- Self-lubricating sheave
- Slotted pin shackle eliminates fouled lines
- Two way head post
Applications:
- Mainsheet
- Halyard
- Vang
- Spinnaker control lines on off-the-beach catamarans, one design classes and sportsboats up to 8M(26′)
Materials:
- U.V. stabilized Acetal sheaves
- Impact and U.V. resistant, fiber reinforced Nylon cheeks
- Grade 316 stainless steel bearing race
- Grade 316 stainless steel load strap and head fitting
Specifications:
- Sheave Ø: 40mm(1-9/16″)
- Max. Rope Ø: 10mm(7/16″)
- Pin Ø: 5mm(3/16″)
- M.W.L.: 600kg(1,320lbs)
- B. L.: 1,200kg(2,650lbs)
- Weight: 135g(4.8oz)
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