The Line 6 DL4 MkII guitar effects pedal includes all the sounds and features of the original DL4 delay modeler, while also introducing an updated slate of effects. The 15 new MkII delays were pulled from the Line 6 HX family of amp and effects processors, and the 4-Switch and 1-Switch loopers offer up to 240 seconds of record time (expandable to several hours using an optional microSD card, sold separately).

Additional features on the DL4 MkII include an XLR microphone input, MIDI In and Out/Thru connectors, four heavy-duty footswitches with colored halo rings, three bypass options and a jack for connecting an optional expression pedal or two external footswitches (sold separately). The DL4 MkII effects pedal is also smaller and lighter than the original DL4, providing extra convenience for modern musicians.