this review title is: they don t even fit together never mind interlock do not waist your time and the content is: so disappointed these are rigid hard plastic that are completely unable to lock together because they are not flexible at all i couldn t wait to get these i had them in the s and loved themtrust me these are not them ridiculous.there are other information for this review, one is this reviewer did purchase it and the other is 0 people think this review is helpful.