according to API 1529
: 1998 type C - Grade 2
Black, smooth NBR rubber,
resistant to aviation gasolines and jet fuels having
an aromatic content up to 40%.
Synthetic textile fabrics.
Smooth, black colour, antistatic (R between 1000 Q/m
and 1 MQ/m) CR rubber, resistant to abrasion, oil, fuel,
ozone and weather.