a spring - type embroidery hoop or knitting ring includes a plastic annular member with an interiorly - grooved surface , a spring - loaded member that fits securely with the free ends of said spring - loaded member projecting radially outwardly , and a locking member that restrains the free ends of the spring - loaded member from separating from one another more than a fixed spacing distance . a squeezing manipulation of the free ends causes them to be spaced from each other a distance less than the fixed spacing distance , while concomitantly reducing the circumferential dimension of the inner ring , so that the inner ring may be moved in or out of the groove in the outer ring in a controlled manner .