Prefilters | McMaster-Carr

	Trade Size Trade Size

	Thickness Thickness

1/2"

	Diameter Diameter

	Pipe Size Pipe Size

3/4
1
1 1/2
2
2 1/2
3
4
6
8

	For Use With For Use With

Air

Water

	Maximum Temperature Maximum Temperature

180° F

Not Rated

	DFARS (Defense Acquisition Regulations Supplement) DFARS (Defense Acquisition Regulations Supplement)

DFARS Specialty Metals
COTS-Exempt

	REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) REACH (Registration, Evaluation, Authorization and Restriction of Chemicals)

REACH Compliant

	RoHS (Restriction of Hazardous Substances) RoHS (Restriction of Hazardous Substances)

RoHS Compliant

	Screen Material Screen Material

Steel

Stainless Steel

Plastic

	Connection Material Connection Material

Steel

Stainless Steel

Plastic

	Height Height

	Screen Opening Size Screen Opening Size

	Thread Type Thread Type

NPSM

NPT

	Maximum Size Maximum Size

	Minimum Size Minimum Size

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125 Products

About Air Filter Efficiency Ratings

These filters are typically used as replacements in HVAC equipment.

All meet UL 900 flame retardance requirements. Actual size is up to 5/8” less than trade size.

Prefilters can be used as a standalone filter or a prefilter that guards your main filter. They’re an economical choice for protecting expensive filters that catch fine particles.

For technical drawings and 3-D models, click on a part number.

Filters
Trade Size	MERV Filter Rating	Filter Efficiency @ 3 Microns	Removes Particle Size Down To, microns	Material	Frame Material	Max. Temp., °F	Pkg. Qty.		Pkg.
1" Thick
12 × 16	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	000000
Prefilters
1/2" Thick
7 3/16 × 9 11/16	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
7 3/8 × 16 1/2	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
8 × 8	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
8 × 10 3/8	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
8 × 22	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
8 3/8 × 11 1/4	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
9 3/8 × 16 1/2	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
10 1/2 × 12	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
10 1/2 × 14	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
11 3/4 × 13 1/2	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
12 × 12	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
12 × 20	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
1" Thick
6 × 6	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
7 × 7	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
8 × 8	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
10 × 10	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
10 × 16	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
10 × 20	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
10 × 24	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
10 × 25	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
10 × 30	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
12 × 12	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
12 × 18	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
12 × 20	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
12 × 24	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
12 × 25	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
12 × 30-5/8	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
12 × 36	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
14 × 14	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
14 × 18	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
14 × 20	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
14 × 24	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
14 × 25	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
14 × 30	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
15 × 20	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
15 × 25	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
15 × 30-5/8	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
16 × 16	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
16 × 20	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
16 × 24	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
16 × 25	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
16 × 30	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
16 × 32	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
18 × 18	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
18 × 20	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
18 × 22	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
18 × 24	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
18 × 25	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
18 × 30	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
18 × 36	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
19 × 27	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
20 × 20	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
20 × 22	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
20 × 24	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
20 × 25	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
20 × 30	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
20 × 32	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
20 × 36	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
22 × 22	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
24 × 24	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
24 × 30	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
25 × 25	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
2" Thick
10 × 10	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
10 × 20	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
10 × 24	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
12 × 12	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
12 × 24	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
14 × 20	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
14 × 25	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
15 × 20	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
16 × 20	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
16 × 24	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
16 × 25	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
18 × 24	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
20 × 20	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
20 × 24	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000
20 × 25	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
24 × 24	5	20%	3	Fiberglass	Cardboard	180°	12	00000000	00000
25 × 25	5	20%	3	Fiberglass	Cardboard	180°	12	0000000	00000

Made-to-Order Panel Air Filters

Minimum filter size is 4" × 4". Maximum filter size is 23" × 30". Multiply the length × width to determine square inches. Then, see size ranges for pricing.

Typically used as replacements in HVAC equipment, these filters work as a standalone filter or a prefilter that guards your main filter. They’re an economical choice for protecting expensive filters that catch fine particles.

All meet UL 900 flame retardance requirements.

Also Available: Filters larger than 23" × 30". Please ask for 3884T999 and specify material, thickness, actual length, and actual width.

For technical drawings and 3-D models, click on a part number.

1" Thick
Size Range, sq. in.	MERV Filter Rating	Material	Frame Material	Max. Temperature, °F	Pkg. Qty.		Pkg.
16-149 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	000000
150-199 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	00000
200-249 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	00000
250-299 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	00000
300-399 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	00000
400-499 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	00000
500-599 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	000000
600-690 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	000000
2" Thick
16-149 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	00000
150-199 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	00000
200-249 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	00000
250-299 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	000000
300-399 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	000000
400-499 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	000000
500-599 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	000000
600-690 sq. in.	5	Fiberglass	Cardboard	180°	12	0000000	000000

Large-Particle Suction Strainers

For Use With: Water
Max. Temp.: Not Rated

Strainers have a heavy duty construction to withstand a high suction force and wide openings to trap large debris. Commonly used with reservoirs and tanks, they filter particles before they enter your system.

NPSM (National Pipe Straight Mechanical) threads are compatible with NPT threads.

For technical drawings and 3-D models, click on a part number.

With Threaded Pipe Connection

Zinc-Plated Steel Connection
	Pipe Size	Thread Type	Gender	Ht.	Dia.	Screen Material	Screen Opening Size		Each
A	3/4	NPSM	Female	6 1/4"	1 5/8"	Zinc-Plated Steel	3/16"	0000000	000000
A	1	NPSM	Female	7 1/8"	1 5/8"	Zinc-Plated Steel	3/16"	0000000	00000
A	1 1/2	NPSM	Female	4 5/8"	5"	Zinc-Plated Steel	3/8"	000000	00000
A	1 1/2	NPSM	Female	6 15/16"	2 1/4"	Zinc-Plated Steel	3/8"	0000000	00000
A	2	NPSM	Female	4 5/8"	6"	Zinc-Plated Steel	3/8"	000000	00000
A	2	NPSM	Female	7 1/8"	2 3/4"	Zinc-Plated Steel	3/8"	0000000	00000
A	2 1/2	NPSM	Female	4 1/8"	5 15/16"	Zinc-Plated Steel	3/8"	000000	00000
A	3	NPSM	Female	5 5/8"	7"	Zinc-Plated Steel	3/8"	000000	00000
A	3	NPSM	Female	9 7/8"	4"	Zinc-Plated Steel	3/8"	0000000	00000
A	4	NPSM	Female	5 5/8"	7"	Zinc-Plated Steel	3/8"	000000	00000
A	4	NPSM	Female	9 7/8"	5"	Zinc-Plated Steel	3/8"	0000000	00000
A	6	NPSM	Female	9 5/8"	9"	Zinc-Plated Steel	1"	000000	000000
A	8	NPSM	Female	11 7/16"	11 1/16"	Zinc-Plated Steel	1"	000000	000000
B	2	NPSM	Female	3 11/16"	5"	Zinc-Plated Steel	1"	0000000	00000
B	3	NPSM	Female	4 9/16"	6"	Zinc-Plated Steel	1 1/2"	0000000	00000
B	4	NPSM	Female	4 9/16"	7"	Zinc-Plated Steel	1 1/2"	0000000	00000
B	6	NPSM	Female	10 1/8"	9 3/16"	Zinc-Plated Steel	2 1/2"	0000000	000000
C	1 1/2	NPSM	Female	1 7/8"	9 3/8"	Zinc-Plated Steel	5/16"	00000000	00000
C	2	NPSM	Female	1 7/8"	9 3/8"	Zinc-Plated Steel	5/16"	00000000	00000
C	3	NPSM	Female	3 5/8"	11 13/16"	Zinc-Plated Steel	5/16"	00000000	000000
D	1 1/2	NPSM	Female	2 7/16"	9 3/8"	Zinc-Plated Steel	3/8"	00000000	00000
D	2	NPSM	Female	2 7/16"	9 3/8"	Zinc-Plated Steel	3/8"	00000000	00000
304 Stainless Steel Connection
A	1 1/2	NPSM	Female	4 3/8"	5"	304 Stainless Steel	3/8"	0000000	000000
A	2	NPSM	Female	4 3/8"	6"	304 Stainless Steel	3/8"	0000000	000000
A	3	NPSM	Female	5 3/8"	7"	304 Stainless Steel	3/8"	0000000	000000
A	4	NPSM	Female	5 3/8"	7"	304 Stainless Steel	3/8"	0000000	000000
Polypropylene Plastic Connection
E	1 1/2	NPT	Female	3 1/2"	4 7/8"	Polypropylene Plastic	1/4" × 1"	00000000	00000
E	2	NPT	Female	3 1/2"	4 7/8"	Polypropylene Plastic	1/4" × 1"	00000000	00000
E	3	NPT	Female	5"	7 1/8"	Polypropylene Plastic	1/2" X 1 1/4"	00000000	00000