Used these for my baby snakes, and everything is just fine. First, I don't think most commercial breeders and pet stores would sell snakes that are so small that they could even squeeze through that hole. Any snakes capable of squeezing through that are too small for the commercially available pinkies that you're able to provide. Second, like with all escape artists, you have to make sure that the lid is seated correctly. This includes 1.) Making sure that any probes going through the back hole are actually fitted into the hole when you close the lid, 2.) Making sure that the lid itself is in between the retaining edges (I don't have a good term for it, but it's the plastic edging that the lid is supposed to slide into), and 3.) Making sure that the metallic pin that prevents the lid from sliding out is pushed all the way in. And lastly, 4.) Familiarize yourself with how the equipment works and it's weaknesses. For instance, with your thermostat probe (which you ought to be using anyways if you have a heating element), if the chord is not fully fed through the small opening in the back, your lid will not be completely pushed in, and your metal pin will not go all the way down. Then run actual tests to see if you can lift the lid or be able to pull it out with little effort. This tank is a reasonable grow-out tank for snakes. For some reason, there has been a recent change in the sentiment of snake-keeping that 20 gallons is the minimum for babies. Not sure where "bigger the better" sentiment come from, but I tend to be leery of "rule of thumb" when it comes to anything pets. With a tank this size and with its overall dimensions, I'm not wasting substrate, I can effectively look for my shy specimens when it comes feeding time, and I can easily monitor my snakes (important since they are escape artists). I've had more snakes escape from tanks that were ultimately meant for larger specimens, since most decent-looking tanks that are 20gallons and above are built for larger snakes.

Works great for my needs. I keep one of my Asian forest scorpions in this. It is mostly a pet hole but does occasionally venture out to enjoy the space this provides.

It was warped so bad to the point the lid didn't close.

I have three of these tanks and use them for my larger terrestrial tarantulas. They give plenty of ground room and place to put hide and water dish. I have had no issue with escape or legs hanging up on mess lid. Lid has a pin that locks it closed which has kept anyone from escaping. I love the low profile so tarantulas can not climb to high on glass and risk a fatal fall. I will definitely be upgrading all my terrestrial tarantulas to this enclosure in the future as they grow. I do not recommend for Tarantulas under 4”-5” leg span they are just too large of an enclosure and not really necessary for smaller T’s hope this helps. :)

Great product for building a feeder colony of isopods, used for powder blue isopod to supplement other cages populations

I bought this for my baby Andean milksnake, and it's the perfect size for him. Note that as packaged it is not escape proof for baby snakes. There's a cutout for a cord and the sliding top has some give at the back that a baby could force their way through. My solution was to run the probe wire for a thermostat through the cable notch, and use an Imaginarium cage clip on the back. It's very secure now. I'll try to link to the cage clip (not sure if they strip out URLs in reviews). https://www.petco.com/shop/en/petcostore/product/imagitarium-screen-cover-clips

Perfect low profile tank with slide out lid I can lock

I use this case for my pet tarantula. In regards to the gap that some have talked about. It is a gape for a power cord. Its about 1/8" wide. See photos.