This is a bag holder designed to make it easier and more comfortable to carry lots of plastic bags. I've printed the 20 mm version using ABS in 0.25 mm layers. The 20 mm version is strong, able to support at least 10 Kg without much flex. The 13 mm version is weaker, but might be useful for people that can't carry much weight and/or have tiny hands. I haven't tested, but I believe (based on the tests with the 20 mm version) that the 27 mm version is very strong and probably can hold more bags than a normal person is able to carry.