The thirty different metric bits all fit into the single handle with a 4mm hex socket. The bits are retained by a magnet so cannot easily fall out, but a well fitting screw-head, eg a hex Allen screw, can trap the bit enough to overcome the magnet.
This is not intended as a heavy-duty set, and the slim grip on the driver handle does not encourage great force. The swivel top has eased with use, and now, after some initial stiffness, allows the driver body to rotate quite freely when spinning the screws by fingertip while bracing the top in the palm of the hand.
The plastic case is a resilient polythene, and it still grips the tool bits rather too strongly, even after several weeks of intensive use. I think the weakest parts are the clasps that hold it shut, but so far they have survived.
The product description has some minor errors (as I write) and I show the corrected lines below
4 cross slot bits, sizes: no. PH00, PH0, PH1 and PH2
7 x hexagonal bits, sizes: 1.0, 1.3, 1.5, 2.0, 2.5, 3.0, 4.0 mm
Tri-winged security bit: no. 0 (3.0mm)
I've owned a similar metric set from Draper for a number of years, but recently lost it, and this replacement fills the gap in my small-tools box perfectly.
For simple, long, slim jeweller's screwdrivers I still also use my seven-piece Moore & Wright jewellers screwdriver set in the plastic tube - alas not listed on Az.