Having received my "selection" of broken solar cells, I will give my honest opinion as far as I can regarding their suitability for building your own panel - that is DO NOT BOTHER!! I am new to this so hoping I am not upsetting anyone with this comment, it is just my opinion, that this is not an effective way of doing things. I brought a selection of sixty plus broken cells, these were nothing but shards the largest fragment being about 1" x 1". I managed to piece some back together to form partial cells but am not going to pursue this any further as I see it as uneconomical and a waste of time. My thoughts only for any other new people who are considering buying these broken solar cells listed on an auction site!! They are as described but that is about it. I will (for now anyway) stick to factory produced panels with a warranty!