As a cheap and casually used terminal block I think quality is also a point. The joined end will come off if you use the fitted connector. It seems to sell the board for the edge, but it is troublesome so I use it by the necessary number + 1. It is better to be careful not to lead to breakage as the square washer rotates and deforms the plate part at the corner at the time of screw tightening. (Although other terminal blocks are similar in this respect)