I've had these set up on my helmet with some genuine Peltor ARC rail adaptors, unfortunately i cant seem to find the original ones that were supplied with it, however, if found they'll be included!  On the pictures you may note that I've 'filled' the 'lugs' that the arc rails attach to on the sides of the ear cups, this just improved the stability on the Peltor Arc rail adaptors.  Cords have been taped (tan) for durability.

They've worked well for me and are still in very good condition.

Asking for £25, this will include PayPal transaction fees.  Postage will be £3.90 second class signed for.

Let me know if you have questions or need any more pictures.

Cheers.