Thistle Parts

Low-friction Carbo Air blocks are lightweight, strong, reliable—and affordable. Companions to the popular Harken Black Magic block line, these small, compact blocks have very high working loads for safe, easy trimming. Sheave: 40 mm / 1 9/16 in...

40mm single block from the Ronstan All Purpose (AP) blocks range, a great all around solution for a variety of rigging applications. Self-lubricating Acetal polymer sheaves running on polished stainless steel races perform equally well with dynamic loads...

40mm single block with becket from the Ronstan All Purpose (AP) blocks range, a great all around solution for a variety of rigging applications. Self-lubricating Acetal polymer sheaves running on polished stainless steel races perform equally well with...

Now you can enjoy the flexibility of setting up your rig exactly as you want. Ronstan is the only company that offers a 40 mm ratchet block with both auto and manual engagement models. This manual version allows the ratchet mechanism to be switched on or...

Carbo Ratchets allow sailors to hand-hold loaded lines and offer balance between holding power and controlled easing. On/off switch operates from both sides. Standard grip: medium/light air; 10:1 holding power. Sheave: 57 mm / 2 1/4...

The Frederiksen ratchet block is legendary. It is light and very strong for optimal performance. The ratchet has a small distance between each click to enhance control of sheets. This is the ideal Laser mainsheet block. From Ronstan: The patented...