For those exploring two-heddle weaving, Kromski offers a choice of heddle blocks.

You can leave the original block in place and add a Second Heddle Block Set for occasional double-heddle projects. Alternatively, opt for the Double Heddle Blocks, which replace the single set, keeping your loom always ready for a second heddle. Either way, double weaving means double the fun!

See our tutorial here http://kromskina.com/double-heddle-poncho/