Pecs Clothing Following feedback from our customers, all images are now larger, 4.5cm squares, making them easy to see whilst still being a good size to hold and use. Made from plastic, so highly durable, waterproof and resistant to grease. Boards and symbols all come with good quality sticky backed Velcro, easy assembly - simply pop symbols out and stick velcro on. Ready to use in 2 minutes! Uses only high quality picture communication symbol images by Mayer-Johnson (used with permission). These are the most common visual symbols to be used to support the learning and development of those with learning disabilities. All corners have been rounded to reduce scratches.