the small plastic wallet is called a Jimi and most bike stores carry them. I use my jimi to carry an expired drivers licence (well the address and number are still the same even though it's expired), a credit card with a low limit so if I lose it I will be out a minimal amount but at least I can cover an emergency with a downpayment, a couple of singles and a twenty for water and or food. It fits in my underseat wedge bag along with a spare tube, co2 gun and two cartridges, tire irons, compact park multi tool, a small bayer aspirin tin with a couple of aspirin, a couple of anit histamines and a couple of band aids, a small pcket knife, and an emergency gu packet. That plus two bottles, one always of plain water for drinking washing, first aid, whatever, in my jersey pocket cell phone, key, bandana, and a zip lock bag with a packet of chamois buttr, an energy bar, and a few cliff blocks.
Most of my rides are three hours but the energy bar, like the cliff bloks and gu are mostly there in case I feel a bonk coming on.
I have thought about a bento bag but decided that there wasn't quite enough space, and besides if the stuff is there where I can get at it easily, it will be easy to eat so best to do without because if I have to stop to fumble for a bar or gel, I will stop and step down long enough to drink, catch my breath, eat part of the bar, and break up the rest and put it back into my pocket for later.
This is my standard set up and has worked on local training and charity rides from 2-4 hours as well as cross rides and rides of five hours or more.
marni
Katy, Texas
Trek Madone 6.5- "Red"
Trek Pilot 5.2- " Bebe"
"easily outrun by a chihuahua."