Electronics-Salon 10PCS Prototype PCB for Arduino UNO R3 Shield Board DIY, Combo 2mm+2.54mm Pitch.

I bought this prototype shield because of the array of high-density holes. After constructing a shield with this board, I've decided the HD array doesn't help much, if at all. Since many components have leads on 0.1" centers, any of them installed in that area need to have their leads re-formed to fit. More often than not, I found I needed to spread the leads because the physical size of the component didn't lend itself to bringing them closer. As a result, I actually got poorer component density than I would have achieved with a shield with 0.1" hole centers everywhere.

The main field of solder points are on a spacing of 12.5 to the inch, not 10 to the inch. This is usable so long as the components have flexible leads, but integrated circuits require the 0.1 inch spacing. Spacing outside the main field are at 0.1 inch spacing. The spacing for the header pins are done right to match up with Arduino boards at 0.1 inch spacing. OMS ProtoPro-B are sadly no longer available.

I've use two of them so far and it's great to have the smaller pitch area on the board for things like TO220-5 components. Everything lines up well so I couldn't be happier with the purchase.

These are great, i specifically for them smaller SMD offset. Great for putting a nodeNCU or D1 Mini on it

Standard DIP ICs will not fit in the breadboard area. The spacing is 2mm, not 2.54mm (.1 inch). I know it says that in the description but it is easy to overlook.

Boards are great for setting up prototypes along with the Arduino Uno. Easy to solder and good quality.

Great for building your own custom designed Arduino Uno shields

Nice board layout, very flexible in designing replace components