Thermosky 3/4 Orthotic #1581 - One PairThermosky 3 4 Orthotic #1581 One Pair ThermoSKY orthotic material is a high quality, cross linked EVA foam designed to absorb shock while maintaining its shape. ThermoSKY retains its structural integrity, assuring that your orthotic will not bottom out under stress. ThermoSKY combines well with Plastazote to produce a lightweight orthotic that will comfort and protect your patients with diabetes or arthritis.