Pozi pan head bolts (Machine screws), M6 x 30 steel, bright zinc plated.  M6 (6mm) x 34.5mm long, pack of 100 nuts and 100 bolts = 200 items in total.  These are standard M6 metric thread (metric coarse) which has a 1.0mm thread pitch.  Overall length 34.5mm, length of the threaded part from the end to under the hexagon head 30mm, thread diameter 5.75mm, diameter of head 11.9mm.  The nuts measure 10mm between flats, so you need a 10mm spanner or socket.
Pan head screws have the top edge of the head rounded over (cheese head screws are similar but they have a flat top with a right angle edge to it, and the head part is slightly thicker).

FREE DELIVERY TO ENGLAND/WALES/SCOTTISH LOWLANDS MAINLAND.  Next working day courier delivery available as an upgrade to England and Wales mainland only at a small extra cost:- if you take this option you MUST tell us a safe place or neighbour where it can be left if you are out when they call- they won’t leave it otherwise.