TYPE 1 WOOL Naturally flame-resistant, Type 1 wool felts will still burn when exposed to an open flame, although they will self-extinguish once the flame is removed. Material is naturally abrasion- and vibration-resistant.

POLYESTER Economical synthetic felt. Ideal as a replacement for wool; however, polyester has lower sound-deadening, compression recovery, and wicking properties than wool.

FELT COMPARISON CHART

Material

Wool Fibre Content (%)

Durometer

Hardness

Tensile Strength (psi)

Resistance (psi)

Compression Recovery (%)

Max Temp (°F)

Abrasion Resistance

Vibration Absorption

Acid Resistance

Alkalai Resistance (Dilute)

Solvent Resistance

Type 1 Wool Felt

Grade 32S2

100

75-85A

Extra-Hard

500

48

99

200

Excellent

Ultra-High

Good

Fair

Excellent

Grade 24S2

100

55-65A

Hard

500

46

99

200

Excellent

Very High

Good

Fair

Excellent

Grade 20S2

100

45-55A

Medium

500

40

99

200

Excellent

High

Good

Fair

Excellent

Grade F1

95

30-40A

Extra-Firm

500

33

99

200

Excellent

High

Good

Fair

Excellent

Grade F3

85

30-40A

Firm

400

22

99

200

Excellent

High

Good

Fair

Excellent

Grade F5

95

20-30A

Medium

400

18

99

200

Good

Medium

Good

Fair

Excellent

Grade F7

80

20-30A

Medium

250

12

99

200

Good

Medium

Good

Fair

Excellent

Grade F10

95

15-25A

Soft

225

8

99

200

Fair

Low

Good

Fair

Excellent

Grade F13

75

15-25A

Soft

225

2

99

200

Fair

Low

Good

Fair

Excellent

Grade F26

45

5-15A

Soft

75

2

99

200

Poor

Very Low

Good

Fair

Excellent

Synthetic Polyester Felt

Polyester

-

75-85A

Medium

500

-

85

300

Excellent

Ultra-High

Good

Fair

Excellent