Chillas are either Cold or Hot packs. Water absorbent cystals are trapped between layers of breathable fabric: either heat in the microwave on medium at 30 second intervals until the desired temperature is reached, or chill to freezing . It's up to you. You are simply playing with the temperature of the trapped crystals
As a cold pack, the Chilla is a remedial and preventative first aid treatment for strains, soft tissue bruising and swelling. Perfect for the application of R.I.C.E post traumatic treatment ('I' = ice, 'C' = compression)

Construction
Cooling Agent: Water - held in water absorbing crystals, released through evaporation and cooling or heating whatever it contacts.
Fabric: Shrinkproof, colourfast and rot resistant.
Crystals: Non-toxic, inert, hold more than ten times their volume when immersed in water. They shrink back to their original state over a period of days as water loss occurs and have a life of five years.
Velcro: Generous attachments (some elasticised) to fit all shapes and sizes.

Uses
The Chilla has two cooling functions that overlap:
Ice cold as a remedial and preventative First Aid treatment for tendon strains, knocks and swelling and secondly as a cooling down treatment - similar to hose tubbing or standing in water.
As a heat pack to promote an increase in circulation.

Directions For Use
Open Chilla out and lay flat in a tub of the coldest, cleanest water available. After a few minutes begin moving the swelling crystals evenly along the channels. When used for the first time swelling takes a little longer. When channels are nearly full but not taut, (about 4 minutes), remove from water, use or store in cool environment. Store in freezer and transport in a cooler bag or chilli bin. Spray or dip in water just before use - cold is conducted through wet fabric more effectively. Can be left in a freezer and microwaved to soften slightly.
To use as a hot pack, hydrate as above, microwave on medium for 30 second intervals until the desired temperature is reached.
If wrap is too taut (over soaked), allow water to evaporate out, i.e lay over a towel rail or leave in a warm location.

Care
When not in use store in freezer or allow to dry out by laying flat in warm airy situation. All water will evaporate leaving hard crystals. Store in dry place ie. the hotwater cupboard or store in the freezer and microwave to soften slightly. The Chilla will last years when used sensibly. Respect that the fabric is fine to allow evaporation to occur readily. Don't throw on the ground where it may get cut or punctured or leave wet in a plastic bag for days on end.

Guarantee
The manufacture of Chilla wraps is warranted for one year providing proof of date of purchase can be shown.
The crystal inside has a life of 5 years and all materials used in the construction are synthetic so will not rot.