Air and Foam Flotation
Functional areas of the cushion are created by three types of foam: soft foam for the decubitus-sensitive area of the ITs; medium foam for the thigh trough, pelvic bucketing and pre-ischial bar; and firm foam for the perimeter and the medial thigh separator.

Bonding Evolution foam to coated fabric makes the cushion hold air. A valve releases air to immerse the user in the foam, the foam conforms to the user, and the users weight is distributed over the surface of the cushion.

Independent research has shown VARILITE air-foam floatation to be the #1 impact and vibration dampening technology (RESNA 2000).

Positioning Supports
Positioning supports improve stability, which is important for users with compromised sitting balance or who transfer frequently. Multi-stiffness foam provides support as the user is immersed in the cushion. Medial and lateral supports minimize internal and external lower extremity rotation. Pelvic bucketing and a pre-ischial ridge help maintain pelvic position, and thigh troughs promote a neutral femoral position.

Four-way-stretch Fabric
Evolution foam is bonded to four-way-stretch knit fabric for maximum conformity during immersion. The fabric is puncture and water resistant.

PSV
VARILITEs PSV takes guesswork out of cushion adjustment and makes it automatic Evolution PSV uses VARILITEs revolutionary new Pressure Setting Valve (patent pending). The PSV works by sensing the amount of internal cushion pressure. As air is released, internal pressure decreases and the user is immersed in the cushion for effective pressure distribution.

The PSV is marked with three pre-set positions, which provide the best range of immersion for most users. The therapist determines the PSV position that results in optimal pressure distribution for a client. (A therapist can mark a different position on the PSV if the user falls outside the pre-determined range.)

Sitting on a fully inflated Evolution PSV, the client simply opens the PSV to the appropriate position. When the PSV senses that enough air has been released, it automatically shuts off the flow. The client closes the PSV. Adjustment is simple and consistent.

Ease of use improves user compliance. A therapist can select the Evolution PSV with confidence, knowing that a client or caregiver can adjust the Evolution PSV easily for optimal pressure distribution. The first time. Every time. onsistent.

Standard Valve for Adjusting Air Volume
Sitting on a fully inflated cushion, the user opens the valve and releases air, closing the valve when sitting on approximately 1/2 inch (13 mm) of air and foam.

Cover
The Evolution is available with a mesh or incontinence cover with breathable four-way-stretch material. Reticulated foam inside promotes air exchange and improves pressure distribution. The underside is a rugged nonslip material with hook and loop for added security. Evolution cover meets ISO 7176-16 ignition resistance standards for upholstered wheelchair components. Machine washable.

Wedge
A modifiable closed-cell foam wedge is available as an accessory with each Evolution. Our Wedge reduces the seat-to-back angle, which increases the weight-bearing load on the back of the thighs and decreases the load on the buttocks. The 2 inch (5 cm) tapered wedge trims easily for custom fitting to meet individual needs.