Acme Duplex™
Precision Sash Balance

Manufacturing

The authentic, 🇺🇸 US-made choice for wholesale window hardware since 1932.

About Us

Old American man working with wood | Acme Duplex

Since 1932, Acme Duplex has set the industry standard for window sash balance engineering. Our history began with the vision of Aloysius Mantz, who replaced bulky lead weights with innovative spring-based balance technology. This improvement transformed the way architects and builders approach window design.

Our engineering expertise proved its precision even in critical military aviation, ensuring that our mechanisms could handle heavy loads with ease. For over ninety years, we have served as the trusted partner for large-scale window manufacturers and wholesalers across the nation.

We remain dedicated to the durability that defined our brand from the start. As a premier wholesale supplier, we provide the essential hardware that ensures long-lasting and quiet performance for double hung and slider windows. Choose original engineering for your building projects. Acme Duplex is the proven choice for genuine sash balance solutions.

Products

Acme Twin®

Seamless and smooth operation

Acme Twin® - Specifications

Installation: Double Installation; one ACME TWIN® each side.
Limits: Sash width: no limit. Sash height: no limit.

Model	Weight per Cable	Sash Weight
T4.5	4 1/2 lbs	8 to 9 lbs
T6	6 lbs	10 to 12 lbs
T8	8 lbs	13 to 16 lbs
T10	10 lbs	17 to 20 lbs
T12	12 lbs	21 to 24 lbs
T14	14 lbs	24 to 28 lbs
T16	16 lbs	29 to 32 lbs

Duplex® Adjustable

Reliable, customizable solution

Duplex® Adjustable - Specifications

Installation: Installed midway between sill and head jamb.
Single Install Limits: 36" max width, 40" max height.
Double Install Limits: No width limit, 40" max height.

Model	Weight per Cable	Sash Weight (Single)	Sash Weight (Double)
D1	4 to 8 lbs	8 to 16 lbs	16 to 32 lbs
D2	8 to 12 lbs	16 to 24 lbs	32 to 48 lbs
D4	12 to 18 lbs	24 to 36 lbs	48 to 72 lbs
D5	18 to 24 lbs	36 to 48 lbs	72 to 96 lbs

Acme® Overhead Mortise Tape

Superior strength and durability

Acme® Overhead Mortise Tape - Specifications

Installation: Mounted above top sash overhead. Double install recommended for over 16 lbs.
Limits: Sash width: 36" maximum. Sash height: 40" maximum.

Model	Weight per Balance	Sash Weight
O4.5	4 1/2 lbs	8 to 9 lbs
O6	6 lbs	10 to 12 lbs
O8	8 lbs	13 to 16 lbs
O10	10 lbs	17 to 20 lbs
O12	12 lbs	21 to 24 lbs
O14	14 lbs	24 to 28 lbs
O16	16 lbs	29 to 32 lbs

Acme® Side Mortise Tape

Excellent durability and long-lasting performance

Acme® Side Mortise Tape - Specifications

Installation: Single for lighter windows, double for heavier (over 16 lbs).
Limits: Sash width: 36" maximum. Sash height: 40" maximum.

Model	Weight per Balance	Sash Weight
S4.5	4 1/2 lbs	8 to 9 lbs
S6	6 lbs	10 to 12 lbs
S8	8 lbs	13 to 16 lbs
S10	10 lbs	17 to 20 lbs
S12	12 lbs	21 to 24 lbs
S14	14 lbs	24 to 28 lbs
S16	16 lbs	29 to 32 lbs

Industrial Specifications

We specialize in large-scale production of original Acme Duplex sash balances. Our manufacturing processes are optimized for custom wood window manufacturers and bulk distribution partners. We maintain the original engineering standards required for high-grade double hung and slider window applications.