HSS = "High Speed Steel" or pretty much the standard for a basic metal-cutting bit. Do you have a Fastenal in town? You'll get a quality bit there, not some "hardware store quality" stuff.I don't know about the 135* or HSS but I seemed to have best results with 1/8 inch DeWalt split point but I can't seem to find a 1/4 split point. All the local stores have in DeWalt 1/4 are speed tip. I found a 1/4 split point on Amazon and ordered it but what I got was a speed tip. But get this, the product number - DW1316 - is the same. In the pic on Amazon it is split point but on the package they sent me it is speed tip. I emailed DeWalt but haven't heard from them yet.