1/4-20 × 1/2" 內六角螺絲 | 低頭內六角驅動 | 全螺紋 | 合金鋼熱處理黑氧化 (300個/包)

Used a bag of these on a couple of jigs for the drill press. The low head design really helped in tight spots, and the black oxide has a nice, uniform finish. No stripped sockets so far, which is exactly what I needed.

Put together a small fixture plate for a drill press jig and every one of the 300 screws threaded in clean without a single stripped head. The low profile head is perfect for tight spots, and the black oxide coating gives them a nice, uniform look.

The hex socket drive seated perfectly on my Allen key without any wobble, and the low head profile cleared the tight clearance I was working with. Thermal black oxide finish looks clean and uniform across all 300 pieces, no duds in the batch.