This is probably the most practical case I bought so far. It is a Pelican 1150 approximately 3L volume box fitted with tank ring and a dial combi-lock. I choose this over a tank bag because it is waterproof and a secure solution than fabric tank bag that I can leave it on the bike. I added an additional duo USB charging ports to the handle bar to provide power to my accessories.
With this, it resolves my charging solution too. Yes, the tank bag does just fine, but leaving it on the bike does not feel secure.
I use this to hold all the little dingles such as passports, loose changes, sun glasses, a battery bank, my ipad mini. While riding, the battery bank is being charged along with whatever device that requires juice. And when I still require charging, I can lug along the device with the battery bank. I also use the battery bank to recharge my intercom after rides.
I tested them under the rain, so far, all is well except my iPhone 6+ went dead. haha. I didn’t keep it into the box and gamble through the rain, I lost. The rest of my accessories stay dry.
Yamaha Tracer 900 MT09 FJ09 Build n Ride 