Protobloc 2 prototyping breadboard rvfm rh 21 p this prototyping board protobloc 2 breadboard is a prototyping system offering a total of 840 tie points consisting of two sets of 64 rows of 5 inter connected sockets p incorporating the following features protobloc 2 2 64 x 5 grid size 840 number of holes 0 3 to 0 8mm wire size acceptability 3a contact current abs polymer body material silver nickel contact material 4 rows of 50 interconnected sockets suitable for use as power