A Nuc is a nucleus colony of Honey Bees. A standard Nuc comes with a queen laying on four frames of comb and bees at every stage of development. Consequently, a Nuc starts ~45 days ahead of a package and we have been able to get them at equivalent delivery times to the packages so, with our early honey flows, it can make a difference between honey production and just managing to get ready for the winter. A Nuc can transport a few more diseases than a package so you need to deal with a reputable dealer.
A nuc is a living organism and needs such consideration in transport. Transportation is much easier in cool weather. Depending on how far you are traveling after picking up your nuc, you may need to make special arrangements with your supplier. When truckloads of honey bees are transported, whether hives or nucs, they are normally not closed in but the full load is covered with a screen to allow sufficient air exchange and temperature regulation. In transporting hives and nucs, the frames should always ride aligned with vehicle drive direction to prevent frames slapping with every acceleration or braking as this can kill bees.
Typically, your nuc will be closed in just before pickup. Picking up early in the morning before they start flying or late in the evening when they have all returned is best. If weather is hot, you may need to have the top removed and covered with screening. Nucs often have small bee leaks and thus should not be transported within the passenger portion of the vehicle without proper precautions. I like to wrap the nuc in a sheet for transport. The lightly wrapped sheet can also substitute for screening in hot weather transport.
Upon arriving back at your bee yard, immediately place the nuc on the hive stand where it will be located and open up to free fly, whether this is just removing entrance closure or wrap as well. The bees will be in a dither for a while so I like to let the bees settle in for at least an hour or two so that the field bees can orient themselves to the hive location and start going out to work. This reduces the confusion during frame transfer.
When ready to perform the frame transfer, remove the covers and center frames from your hive body. Starting from one side of nuc, lift a frame of comb and bees from the nuc and place is a similar position in the hive. Repeat for each frame, keeping them in the same order and orientation. If there is a feeder in the nuc, lift it out and shake any bees from it into your hive, on top of frames. There may be burr comb in the feeder that should be removed and placed on the ground in front of the hive so that the bees can take back any honey or nectar stored there. Then bang the nuc on the ground to shake the remaining bees into a bottom corner and then dump over the frames in the hive. Fill up any remaining frame spaces, close the hive and leave undisturbed for a few days to allow them to settle in.
In most cases, the nuc box is to be returned to the supplier with the feeder if one was present. The nuc purchase generally includes the frames and no replacement is required or desired.