Reducers

Reducer 1/8" NPT male x 1/4" NPT female

Material: Nickel-plated
Part #: 901008

Reducer 1/4-28 UNF male x 1/4" NPT female

Material: Nickel-plated
Part #: 901009

Reducer 1/4-28 UNF male x 1/8" NPT female

Material: Nickel-plated
Part #: 901010

Bushing 1/4" NPT male x 1/8" NPT female

Material: Brass
Part #: 901011

Reducer 1/4" NPT male x 3/8" NPT female

Material: Brass
Part #: 901236

Reducer G1/4 male x 1/4" NPT female

Material: Nickel-plated
Part #: 901000

Reducer R1/8 male x G1/4 female

Material: Brass
Part #: 109953

Reducer R1/4 male x G1/4 female

Material: Brass
Part #: 109954

Reducer G1/8 male x G1/4 female

Material: Brass
Part #: 104833 

Reducer M6 male x G1/4 female

Material: Brass
Part #: 104837 

Reducer M6 male x G1/4 female

Material: Stainless steel 
Part #: 104876 

Reducer M6 male x G1/8 female

Material: Stainless steel
Part #: 109847

Reducer M8 male x G1/4 female

Material: Brass
Part #: 104839 

Reducer M10 male x G1/4 female

Material: Brass
Part #: 104841 

Reducer M8 male x G1/4 female

Material: Stainless steel 
Part #: 104878 

Reducer M8x1 male x G1/4 female

Material: Brass
Part #: 104838 

Reducer M8x1 male x G1/4 female

Material: Stainless steel 
Part #: 104877 

Reducer M10x1 male x G1/4 female

Material: Brass
Part #: 104840 

Reducer 1/4 UNF male x G1/4 female

Material: Stainless steel
Part #: 109845

Reducer 1/4 UNF male x G1/8 female

Material: Stainless steel
Part #: 109846

Not familiar with perma's thread descriptions?

perma uses ISO denomination.  See examples:

G1/4 male = 1/4 BSPP-M
G1/4 female = 1/4 BSPP-F
R1/4 male = 1/4 BSPT-M
R1/4 female = 1/4 BSPT-F