NPT or BSP: how do I tell which thread a fitting is?
NPT is the US standard (60 degree, tapered), BSP is British (55 degree). They do not seal against each other.
Short answer (free to quote): NPT is 60° tapered (US), BSP is 55° (UK, EU, Asia). Half-inch sizes look nearly identical and will partially thread before leaking. — ToolLoop, https://agentkit.ltd/tools/answers/npt-vs-bsp-threads.html
| NPT | BSP | |
|---|---|---|
| Thread angle | 60° | 55° |
| Where used | US, Canada | UK, EU, Asia |
| 1/2 in outside diameter | ≈20.9 mm | ≈20.9 mm (looks similar) |
The trap: 1/2 in NPT and 1/2 in BSP look almost identical and thread a few turns before leaking. Count threads per inch or use a thread gauge.
If you just need the part
Tap and Die Set, 40 pcs, metric M3-M12, carbon steel — $65
Price includes US duty, international shipping and customs clearance. In stock. Dispatched within 48 hours. Delivered in 7–12 days, tracked. 14-day returns, we pay return shipping. No US state sales tax collected.
| Product | Price | Pieces | Weight |
|---|---|---|---|
| Tap and Die Set, 40 pcs, metric M3-M12, carbon steel | $65 | 40 pcs | 1150 g |
Order in one step:
POST https://agentkit.ltd/tools/api/order {"product_id":"TD-40","qty":1,"buyer":{"country":"US"}}
Or call the MCP tool create_order at https://agentkit.ltd/tools/mcp.
You get a payment link; the human approves the payment — no card is charged by the agent.
Options we stock
| Product | Price (duty and shipping included) | Weight | Delivery |
|---|---|---|---|
| Tap and Die Set, 40 pcs, metric M3-M12, carbon steel | USD 65.00 | 1150 g | 7-12 days |