Physical size feels like it should be small rather than micro, but it fits only a log book and a thin trackable, which is why it is listed as a micro. If stealth isn't your 'thing', as in, the more stealthy you try to look the more obvious you feel you feel you are being, then this could be ideal. Whilst the general area can be a high muggle zone, a moment of patience and observation can result in a moment of seclusion - long enough to find and sign minus the muggle pressure.
Bring own pen/pencil. No room for swag, but a thin trackable might fit.