The wooden layer used with the SpiderJack 2.1 brake lever is made of pock wood, an especially hard and heavy wood.
More information about pock wood:
The SpiderJack brake lever is made of pock wood, an especially hard and oily wood. Most of the precious pock wood comes from Central America, traded only under strict legal control. Its botanical name is Guajacum. Depending on its geopgraphical origins, Guajacum carries additional names like coulteri (Mexico) or officinale (Antilles). In Europe the name ‘pock wood’ derives from the times, when its resin was used in the fight against pox. Because of its high proportion of oil and its great density, pock wood is a well known natural product featuring an outstanding abrasion resistance. Even the drive shafts of steam ships were mounted on pock wood. It is well known, wood is a poor conductor of heat, even more so with pock wood. So naturally, controlling a rope with the SpiderJack s pock wood brake conducts very little heat.