Bests & Worsts Reviews from Amazon

I ordered four of these bottles. Three purple and one black. The filter in the purple bottles screws into the cap per the description and seems to work well. The filter in the black bottle was of a different type. It had a ring around the top edge and no thread in the middle to screw it into the cap. The problem with the filter not screwing into the cap is that in order to fill the bottle you have to take the filter out by either reaching into the bottle or by tipping the bottle over dumping any remaining water into your hand which has to be there to catch the filter as it falls out. Either refill/removal method is unhygienic and is prone to losing the filter or having it fall into the sink or other place at which you are filling the bottle. On the theory that the black bottles have a different type of filter I returned it and ordered another purple bottle. Unfortunately, the replacement purple bottle also had a filter that does not screw into the cap. The same item apparently comes in different styles and there is no way that I have found to tell which ones have the filter that screws into the cap and which don't when placing the order. The UPC codes for the two different bottle (filter) types is the same. However, on the UPC block of the bottle package there is what appears to be a model number. The bottle with the screw-on filter has a model number of L51783830A. The bottle with the non-screw filter has model number of L51783830B. The Amazon description of the bottle lists the model number as 1783830. It does not indicate whether it is the A or B version. The cap of the B model has a thread receptacle, so it should accept a filter that has a screw thread, but the filter that comes with the bottle does not have that thread. The package of the screw type bottle has a copyright dated 2010. The non-screw bottle's package has a copyright of 2011. I don't know if I can generalize, but it appears that newer bottles do not come with the screw-on filter. The picture available for the replacement filters shows the screw on thread on the top of the filter. I hope that doesn't change when I replace the filters. I am going to return the latest purple bottle.