The 53019000 is a silver gray GMP-GL 7 Counter Nut with collar and PG connection thread for maximum mechanical stability. For locking SKINTOP? cable glands in boreholes without thread. Supporting surface for spanner means scratches on the housing are avoided. The SKINTOP? GMP-GL 7 hexagonal locknut made of polyamide, glass fiber reinforced, is used where cable glands are attached but there is only a pass-through whole. When the cable gland is fixed in a thread, a higher protection against vibration can be attained with this locknut.