These custom slotted machine screws were made at a smaller 150 piece quantity for our architectural design customer.  They were made domestically using 18-8 stainless steel material with a relatively fast turnaround time of 2 weeks from order.  We replicated a sample part provided by our customer in the absence of a drawing.  1/4-20 thread pitch was incorporated with the thread length at 1-1/2 inches.  Our internal part number for this part is STS-1524-I.