The fabric attachment system is low-tech, but that seems to be helpful, as it can adapt to seat rails of different widths. One fancier option you might see on more expensive seat bags is a quick-release mount that you install under your saddle. But those have a fixed width, and therefore can fit under seats with only those exact specs. Brooks saddles, for example, are too wide for these mounts.
Main types of bicycles are road, mountain, commuter/comfort and fitness bikes. There are more specific types and other names for bike types within that, such as urban bikes (same as commuter bikes), cruiser bikes, dual-sport bikes, hybrid bikes, fixed-gear bikes, cyclo-cross bikes, adventure road bikes (aka all-road bikes, gravel bikes), road bikes, touring bikes and specialty bikes, like BMX.
This gentleman is a true professional!! He is an ex-Marine and I will tell you that he represents them well. He is honest, knowledgeable and extremely reasonable. He repaired my son's bike while I waited and went over the whole bike and made the required adjustments replaced an inner tube and all for 20 dollars!!All the kids in the area pass by and call him by his first name. I will recommend him to everyone I know since there are very little of them out there!!
Whether you ride a single, 7, or 10 speed bike or anything in between, you will need a slightly different chain. The major difference is that they come in varying widths to accomodate the different spaces between the gears, but quality of construction is also a factor in choosing a chain. Inspecing the chain should be a part of your regular cycle maintenance procedure- It’s important to keep a chain well lubricated, but oil will also attract dirt and so different oils for specific riding conditions are available. Remember to clean your chain regularly to get the longest life out of it and the gears.