IPT or NPT pipe thread
The NPTF (IPT) male will mate with the NPTF or NPSM female. The NPTF (IPT) male has tapered threads and a 30° inverted seat. The NPTF female has tapered threads and no seat. The seal takes place by deformation of the threads. The NPSM female has straight threads and a 30° inverted seat. The seal takes place on the 30° seat.

SAE 45 degree flare
The SAE 45° flare male will mate with an SAE 45° flare female only. The SAE male has straight threads and a 45° flare seat. The SAE female has straight threads and a 45° flare seat. The seal is made on the 45° flare seat.

SAE inverted flare
The SAE 45° inverted flare male will mate with a 42° inverted flare female only. The male has straight threads and a 45° inverted flare. The female has straight threads and a 42° inverted flare. The seal is made on the 45° flare seat on the male and the 42° flare seat on the female.

JIC 37 degree flare
The JIC 37° flare male will mate with a JIC female only. The JIC male has straight threads and a 37° flare seat. The JIC female has straight threads and a 37° flare seat. The seal is made on the 37° flare seat.

SAE straight thread o-ring boss
The o-ring boss male will mate with an o-ring boss female only. The female is generally found on equipment ports. The male has straight threads and an o-ring. The female has straight threads and a sealing face. The seal is made at the o-ring on the male and the sealing face on the female.

This information has been provided by Couplamatic Systems. Couplamatic Systems Inc. has been serving the hydraulic hose and coupling industry for over 40 years. Couplamatic Systems Inc. was known to the industry as House of Hose up until 1996 when the name was changed to Couplamatic Systems Inc. CSI began as a modest business venture and today has grown to be one of the nation's most comprehensive providers of hydraulic couplings, hose, adapters, crimping equipment, and accessories.