Home / Springs and Accessories / 4-blade drill 50 mm for 16 mm spring4-blade drill 50 mm for 16 mm spring Request a Quote Home / Springs and Accessories / 4-blade drill 50 mm for 16 mm spring4-blade drill 50 mm for 16 mm spring Request a Quote 4-blade drill 50 mm for 16 mm spring for Allround+. To mill overgrown pipes.