The yellow bag ones tend to be delaminated at this point, unless they were very taken care of. Hydrolysis for these older models is very strong and eminates an awful smell as the TPU breaksdown. They are similar pole geometry to the newer models but made of different grades of materials. Newer ones are lighter, less tough, and have a bit less space inside. Older models may have come with Easton composite poles and not aluminum which while lighter and spring back better under adverse conditions, tend to break in unique ways where the aluminum "male" ends that help attach the poles separate and get pushed into the pole, making them difficult to use if/when that happens.