Amtech 12pc Drain Rod Set The Amtech 12pc Drain Rod Set is made from polypropylene gives the rods the strength needed as well as the flexibility to get around bends. The rods are joined together with screw couplings that tightened in a clockwise direction. Comes with a rubber plunger and a double worm screw ends giving you plenty options regardless of the blockage. Each rod is 920mm long, with this set you have 10 rods, giving you 9.2m of unblocking power.