What To Pack: Day Trips
If you're going to be out and about during the day, and may not have access to an electrical outlet, there are a few options you can consider. The first is the use a battery operated electric pump; most electric pumps out there come with the battery pack, but you'll have to remember to bring your battery pack around.
Personally, I tend to prefer using a manual hand pump, and I use the Medela Harmony for two reasons:
First, the pump is light weight, and compact. I can put the all the components in a zip lock, and store the actual pump itself in my purse. Second, it shares most parts with the regular Medela Pump in Style which is my regular electric pump, so I can have spares on hand.
I've also used my hand pump while on the go - in the car, in the airplane, and while in transit. Basically, when I don't have time to find a "proper" spot to express, but need to stay on my schedule.
I'll also pack my Lansinoh storage bags, and if I am gone for less than 8 hours, don't bother bringing a cooler. Breast milk is extremely stable, but definitely refrigerate or freeze the milk once you get home.
In the end, my day trip checklist looks something like this:
Hand pump handle
Pump parts: Breast shield, pump body, and valve (stored in a ziplock bag)
Bottle with cap
Milk storage bags
One extra ziplock bag
A pen to mark your storage bags
Try to pack your things ahead of time. I know this helps when I have a full day of meetings, or an running off with an early start. There's nothing worse than forgetting a little valve or bottle, and being engorged the whole day.