Lined leather ring with a reinforced thumb-hole and metal pad, which has a plate with a honey-comb pattern, It is onto this plate that the heel of the needle is put in order to push in through the leather.
Context
Although palms didn't appear in trade catalogues until after the mid 1750s, they were probably used for many years beforehand, in some form or other. The Sailmakers palm is so called because it was the kind used by sail-makers and riggers.