Japanese Industrial Standard
1) JIS Tapered Pipe Thread
The Japanese tapered pipe thread connector is identical to and interchangeable with the BSPT (tapered) connector. The Japanese male thread does not have a 30° Flare, and will not mate with the BSPP female swivel with conical seat. The seal on the Japanese tapered pipe thread connector is made on the threads. Use of a thread sealant is recommended. Thread form per JIS B 0203 (identical to BSPT)

Refer to BSPT section for dimensions of threads.
2) JIS 30° Flare (Female Internal Cone Seat)
This connection uses a 60° concave (inverted) seat and British Standard Pipe Parallel threads. They are not interchangeable with BSPP conical seat couplings, because the cone seats are opposite. Thread form per JIS B 0202 (identical to BSPP)

Refer to BSPP section for dimensions of threads.

JIS Thread Specifications
	BSPP Thread	Swivel Hex	Drill	Male Turn Back		Assembly Allowance
Dash Size	T4 BSPP	C (in)	D (in)	L (in)	L2 (in)	X1 (in)	X2 (in)
4	1/4-19	0.75	0.177	0.570	0.606	0.35	0.36
6	3/8-19	0.88	0.275	0.609	0.684	0.29	0.38
8	1/2-14	1.06	0.433	0.726	0.763	0.46	0.53
12	3/4-14	1.44	0.625	0.805	0.842	0.55	0.56
16	1-11	1.63	0.828	0.883	0.881	0.53	0.58