I purchased two of these from sportsmans guide when they were in stock. Just so happened that I got one of each size. The larger fit the grease gun mags well and the smaller worked fine with the 30 round z-mags. Sportsmans guide ones did not offer a style choice and this seller apparently does not either. I have no affiliation with either of those retailers. For under $30 though it seems like a good buy. Build quality was very good on my two examples.
https://www.ebay.com/itm/2528234501...rentrq:8a5b7cdb17e0a7b8bc8cf695fff6fbf4|iid:1
https://www.ebay.com/itm/2528234501...rentrq:8a5b7cdb17e0a7b8bc8cf695fff6fbf4|iid:1
