This is a solid brass 5-40 thread fillester head slotted drive screw with a 1 inch long shank. The shank has 1/2 inch of threads. Quantities are limited, and there are no other lengths or threads available in solid brass (other than the oval head grip cap mounting screw).
When these are sold, they may or may not be replaced depending on the cost and demand. If enough orders come in to justify the expense of a large production run, then they will be restocked. If the sales volume is too low to justify tying up the funds for long periods in slow-moving inventory, then they will not be. Vote with your orders: is up to you!