P-333 MAIN SPRING: 1″ wide, takes 1/2″ to 5/8″ center arbor (center curl), both ends have pear shaped holes, 0.025″ thick. 16′ long. Mostly for single-spring Columbia motors. Please note: Springs are NOT returnable. Extreme caution must be used when working with mainsprings! Not responsible for damages or accidents! Photos show same spring, one with flash, in a 3″ coil.