Topeak defender m1 m2 mudguard setthe defender m1 is compatible with all standard front forks including reverse arch designs the unique quick release attachment system integrates the defender m1 seamlessly with the front of your bike defender m2 has an ultra secure quick release mounting system that easily adjusts from 254 to 34 9mm easily fitting standard and oversized seatposts the two pivot arm articulates for improved tyre coverage and perfect bike fit a stiff engineering grade plas