Quick and easy to use. Simply lay the Simflex Expanding Sewing Guage over your garment and expand it to the desired length for perfectly measured equal distances and accurate spacing from 3/8" to 3 3/8". Expands to 24" overall. The Simflex Expanding Sewing Guage is ideal for shirring, smocking, buttons, eyes, drapery pleats, dress pleats, and tucks and gathers.