Check the listing for details. 5/16-18 BSW M2 HSS Plug Tap, Stanley Plane Restoration Tools. Condition: New. Listed at 15.50 USD. USA inventory with fast free shipping from Florida! 5/16-18 BSW HSS Plug Tap, Stanley Plane Restoration Tools, see #3 in blue on the attached Stanley Plane parts diagram This tap will let you thread and chase the cap iron screw hole A taper tap is best for starting and threading a new hole due to the extended chamfer. If your budget allows for only one tap, I recommend a plug tap. A 5/16-18 plug tap will let you start and thread a new hole and also allow threading a blind hole to within ~1/4" of the bottom. A bottom tap allows chasing and tapping threads very close to the bottom of blind holes. This Plug Tap will allow threading a blind hole to within ~1/4" of the bottom. All taps and dies can be used for chasing. Chasing is the process of rethreading damaged, rusty or paint filled threads. British Standard Whitworth aka BSW is a 55 degree thread angle used by Stanley on this size thread High Speed Steel (HSS) is a broad description of steel grade. A chair made of wood is also a broad description. Is the chair made of soft wood like pine or something hard like hickory? Our HSS taps and dies are made from M2 HSS, a premium grade tool steel utilizing 0.85% carbon (C) 4.15% chromium (Cr) 6.15% tungsten (W) 5.0% molybdenum (Mo) and 1.85% vanadium (V). These added elements provide a high level of hardness and increased resistance to wear. Cutting fluid reduces friction and helps produce smoother threads. *** Please wear your safety glasses *** We will combine shipping on multiple items and refund the savings. Receive a $3.00 refund on this item when you order more than one item for shipping at the same time. MWTCA organization members will receive a 10% discount rebate. Send us a message and let us know you are a member. We will send your rebate promptly through eBay. Thank you for supporting Mid West Tool Collectors Association.