Up for sale is a Massdrop HD6XX with custom cans nickel plated CNC Copper Mass loading mod kit installed. This mod primarily increases and tightens the bass response and opens up the stage. The mod is fully reversible and includes additional foam plugs to adjust the bass to your liking. I do not have the stock pads, but will include the following 3 pairs of pads, all in excellent like-new condition:

-ZMF HD6xx solid lambskin sub-pads ($70 value)
-Geekria velour pads
-AliExpress velour pads that measure pretty closely to stock pads (installed)

Originally box and packaging, as well as stock single ended cable with 3.5mm adapter will also be included.

Information on the mod can be found here:

https://www.audioreviews.org/custom-cans-hd-600-series-mod/

Price includes CONUS shipping via UPS.

Thanks for looking!