Pack of 10, F10A Fuses. Genuine Siba ref 7009463.10 as supplied by most manufacturers of fused test leads.
Fast acting fuses. Rated up to 600V
50KA breaking capacity (these fuses will safely break a fault current of up to 50,000 Amps without rupturing.)
They are not the cheapest fuses that will fit into fused test leads, but they will protect you against high energy faults, shorts etc...
These fuses are 6.3mm x 32mm and fit into fused test leads as supplied by Fluke, Robin and many more. (they go behind the croc clip/probe when you screw it off from the main body)
Always carry a pack of spare fuses, and you won't be caught out on site when you blow a fuse, drop your test leads, loose a fuse etc...etc...