Polyester Thread Buying Guide - Polyester Thread Specifications

Polyester Thread Specifications - Here are U.S. military specifications (MIL-DTL-32072 / VT-285F) for polyester thread. Please note:

Polyester thread sizes are based on the ratio of a fixed length of thread to its weight - not its diameter. This is because thread is spongy and its diameter cannot be measured with calipers.
Bonding slightly increases a thread's thickness and density. As a result, yards-per-pound are reduced.
Average Break Strength is for twisted thread. Monocord threads are 10% to 14% stronger
Metric data is calculated using standard conversion factors. Small rounding differences are inevitable.
Needle size ranges come from other sources and are not part of the mil-spec.

Lightweight and Middleweight - Sizes 15 to 138
Size
Tex	16	35	45	70	90	135
Military	A	AA	B	E	F	FF
Ave. Break Strength
Pounds	1.5	3.0	7.0	11.0	14.5	21.0
Metric	0.7	1.4	3.2	5.0	6.6	9.5
Diameter
Thousandths of Inch	.0047	.0070	.0080	.0107	.0124	.0152
Millimeters	0.1194	0.1778	0.2032	0.2718	0.3150	0.3851
Average Per Pound
Yards	30,000	12,200	9,500	6,000	4,500	3,000
Meters	27,272	11,090	8,636	5,454	4,091	2,727
Needle Size Range
U.S.	10-12	12-14	14-16	16-18	18-20	20-22
Metric	70-80	80-90	90-100	100-110	110-120	120-140