The present invention relates to a synergistic flame retardant combination
for thermoplastic polymers which comprises as component A a salt of
1-hydroxydihydrophosphole oxides of the formula (Ia) or formula (Ib)
and/or 1-hydroxyphospholane oxides of the formula (II)
##STR1##
and as component B a nitrogen compound of the formula (III) to (VIII) or a
mixture of the compounds designated by the formulae
##STR2##
in which the substituents are as defined in the description.