![Ronstan Nylatron Sheave Box – Single Upright Lead Block [RF453]](https://www.durablemarinebattery.com/wp-content/uploads/2026/08/ronstan-nylatron-sheave-box-single-upright-lead-block-rf453.webp)
Description
Nylatron Sheave Box – Single Upright Lead Block
Lead blocks are a low profile solution for leading halyards or other rig sail controls back to cleats or jammers.When mounted in an inverted position, are frequently used as upright leads.
Features:The external tabs can be formed to fit the spar profile before fastening
Applications:Typically used in dinghy spars for control lines such as outhauls
Materials:
- Nylatron® sheave
- Grade 316 stainless steel load housing
Specifications:
Sheave Ø:22mm(7/8″)
Max. Rope Ø:3mm(1/8″)
Max. Cable Ø:3mm(1/8″)
Fastener Ø:5mm(3/16″)
M.W.L.:160kg(350lbs)
B. L.:350kg(700lbs)
Weight:30g(1.1oz) View AllClose
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