These new items are an improvement on the old models, after finally acquiring claw pendants that are an appropriate size to hold the crystals. Each is lit by an internal light-emitting diode circuit, which is in turn powered by a single CR1220 coin cell battery that fits into the clip behind the claw. A silken rattail cord suspends the pendant around the neck, adjustable up to 30″ in length. More colors than the above are also available, but the first six are being test marketed by a merchant at a LARP event. If successful, they will become a stock item.
EDIT: These are now being produced as a standard stock item!
Each pendant is for sale at $15 USD apiece, plus shipping.