thats "zpack blast 18" 3 oz
18 is referring to it being 1800 cubes, that said, it is essentially a cuben sack with shoulder straps. It could be lightened though, remove all but the main pocket, shorten the draw cords etc.
but part of my choice of gear here was that none of it needed to be made. which while not necessary for any gear list makes the numbers easier, because until I/you actually made the gear any numbers are an estimate.
as for signalling device, i was referring to a whistle or a mirror, personally I don't carry either, but thats a lynch-able offense to some people.
ditto with first aid. my general philosophy on first aid is: if it can actually be fixed with a first aid kit, it'll heal fine on it's own. again this is the sort of thing that some people (and fair enough) are absolutely against.
extra clothing. i'm cool with a pair of shorts and a t-shirt but I personally like fresh socks, a lot. and I'm a big sweaty guy, so fresh underwear really makes my morning too.
note this list isn't the absolute minimum needed, honestly if with good weather I don't REQUIRE anything more than food, but I tried to keep it as luxurious as possible in the constraints, which means ideally, I'd like an extra pair of socks or two and some underwear. though without cooking anything there is a spare 2 ounces...
as for temps, I'm aware that the pre conditions of the exercise are that it never gets below 60, I'm just saying that the list given requires those conditions, extra clothes and a bivy of some sort (MLD has a 4.4 ounce one for instance) would really bump up the real world practicality at the cost of going over 1 lb.