Quite compact. The brush seems very gentle and safe for objective lenses. Too bad there is not a plug to prevent dust from coming into contact with the brush when it retracted. On the other side, felt the diameter is not so great in reality. After giving a shot blower on my lens, a brush and a blow of felt, almost clean. He remained in fact a fat little dust that has stood => a mist blow without spluttering and suddenly Felt => nothing. Nickel! I recommend this without hesitation.