TK-421 is absurdly cool just because he's finally a specific Stormtrooper. That inky dinky communicator accessory gives me hope that, someday, they'll do a Sandtrooper with a little ring of droid part, to recreate specifically the "Look Sir, Droids!" guy.
That communicator may be the smallest accessory ever in this line. It's REALLY tiny, yet snaps into its little holster thingie on his belt perfectly.
How lucky the group had one trooper nearby who had a grappling hook and a communicator, and that Luke took his armor. Truly, the force is mystical.