Never use one but do think about it some times and would have the same as I do for my roe sack. Knife and spare, wet wipes, plastic bag, drag rope, gloves disposable, head torch, some string and compact bone saw. If I'm close to the vehicle or can get vehicle to close extraction point it's left in the car except Knife. If going a bit further after Munites or roe, it goes in the roe sack and hardly know its there on the way out. If its full on the way back I'm happy. Fallow well hope for the first case or I work up a bit of a sweat!
When I first started all I had in my pockets was a knife and drag rope but food hygiene has changed all that.