Nomenclature

Ultradur commercial grades are designated by either the letter B or S, followed by a four-digit number.

Ultradur B = PBT
Ultradur S = PBT + ASA

Development grades have the letters “KR” followed by a four-digit number.

The letter behind the number denotes reinforcement or filler materials:

G = glass fibers
K = glass beads
M = mineral

and the number after this denotes the approximate amount of additive, e.g.:
2 = 10 parts by weight
4 = 20 parts by weight
6 = 30 parts by weight
10 = 50 parts by weight

Three-digit numbers represent standard colors and five-digit numbers stand for special colors.

Due to the effects of fillers, standard colors are distinguished by prefixing the numbers

4 … in the case of glass beads
5 … in the case of glass fibers
6 … in the case of flame-retardant additives
7 … in the case of flame-retardant additives and glass fibers
8 … mineral filler