Hard to describe them so the photo is the best option.
Used for Tweaker, Barber Hauler, Jib clew, Up and Down control lines, lot of uses.
Rigging thimbles start having frictional heating and wear problems when there is significant line movement so conventional pulleys are still better for applications such as mainsheet and halyard blocks.
Frictional losses are not as big as one might think, especially when using low friction line such as dyneema. In addition to being lighter and less expensive than conventional blocks, ring ferrules are also less prone to failure since there are no pulleys to crack or bearings to foul.
|Sugegsted max rope size||10mm|
The photo shows a 'Knight Rider' coloured yachting braid