Easton EC70 AX Dropper Seatpost - 27.2 x 400mm 50mm Travel Internal Routing BLKEaston EC70 AX Dropper Seatpost 27. 2 x 400mm 50mm Travel Internal Routing Black. The Easton EC70 AX Dropper Seatpost features a reliable cartridge design internal routing and availability in 2 lengths 350mm and 400mm. The 50mm drop allows for fitment on everything from a wide tired CX bike to modern gravel bikes. Can be paired with drop bar optimized levers or drop bar compatible shifters Cable attaches from either direction for compatibility with