This does not affect your right to an exchange or refund for faulty equipment.
IMP's let you take advantage of the smallest & most marginal placements. Nut heads are made of brass, allowing them to bite into small placements but making them strong enough to resist pulling through. These are soldered directly on to wires, allowing a thicker wire to be used & increasing the strength of the IMP.
The swage on the wire is colour coded for quick size selection, & allows one side of the wire to slide, letting the IMP self equalize when loaded & increasing placement security. IMP's are invaluable for those pushing into harder grades & need to take advantage of all protection options.