![Harken 25mm Wire Block w/Shackle [300]](https://www.bestmarinewiring.com/wp-content/uploads/2026/08/harken-25mm-wire-block-w-shackle-300.webp)
Description
25mm Wire Block with Shackle
Lightweight, low-friction wire blocks carry wire halyards and high-strength control lines on boats of all sizes.
Specifications:
- Sheave: 25mm / 1in.
- Weight: 28g / 1oz.
- Shackle pin: 5mm / 3/16in,
- Maximum wire: 2mm / 3/32in.
- Maximum line: 4mm / 5/32in.
- Maximum working load: 454kg / 1000lb
- Breaking load: 907kg/ 2000 lb
![Harken 29mm Double Carbo Air Block [381]](https://www.bestmarinewiring.com/wp-content/uploads/2026/08/harken-29mm-double-carbo-air-block-381.webp)
![Harken 45mm Triple Element Block w/ SwivelBecket [6241]](https://www.bestmarinewiring.com/wp-content/uploads/2026/08/harken-45mm-triple-element-block-w-swivelbecket-6241.webp)
![Ronstan Series 40 All Purpose Block - Single Upright Lead [RF41171]](https://www.bestmarinewiring.com/wp-content/uploads/2026/08/ronstan-series-40-all-purpose-block-single-upright-lead-rf41171.webp)
![Harken 40mm Carbo Air Block w/Swivel [2636]](https://www.bestmarinewiring.com/wp-content/uploads/2026/08/harken-40mm-carbo-air-block-w-swivel-2636.webp)
![Harken 22mm Double Micro Block w/Becket [227]](https://www.bestmarinewiring.com/wp-content/uploads/2026/08/harken-22mm-double-micro-block-w-becket-227.webp)
![Schaefer Single Aluminum Block – 51mm Sheave [504-05]](https://www.bestmarinewiring.com/wp-content/uploads/2026/08/schaefer-single-aluminum-block-51mm-sheave-504-05.webp)
![Harken 45mm Double Element Block w/Swivel [6238]](https://www.bestmarinewiring.com/wp-content/uploads/2026/08/harken-45mm-double-element-block-w-swivel-6238.webp)
![Harken 57mm Carbo Air Fiddle Block w/SwivelBecket [2622]](https://www.bestmarinewiring.com/wp-content/uploads/2026/08/harken-57mm-carbo-air-fiddle-block-w-swivelbecket-2622.webp)