All rectangular ducts are fitted with flange frames made of sheet angles and braced by cross-wise ribbing. Larger ducts are additionally braced with galvanized tubes( baffles ).
The ducts are manufactured in the following standard sections to standardize the fabrication , shipping and installation procedure:
If a or b ≤ 500, then L = 1250 mm
If a or b > 500, then L = 1500 mm
If rectangular duct ends should be finished otherwise than with flange frames , use the following designations to indicate the required option:
LR — separate frame
BR — no frame (bare end)
Z — blind end

The T-piece ends are fitted with sheet angles, and the entire fitting is braced by cross-wise ribbing. This fitting allows building ductwork with a branch taken off at 90 degrees. The T-piece height a is fixed.
Available materials — Product code examples
T-…- GS -…-… — galvanized steel sheet
T-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
T-…- A -…-… — AW-1050A H24 aluminium sheet

The T-piece ends are fitted with sheet angles, and the entire fitting is braced by cross-wise ribbing. The T-piece helps building ductwork with a take-off branch at 90 degrees and a reduced size. The inlet and outlet sizes are the same.
Available materials — Product code examples
TST-…- GS -…-… — galvanized steel sheet
TST-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
TST-…- A -…-… — AW-1050A H24 aluminium sheet

All T-pieces with round take-offs are fitted with flange frames made of sheet angles and braced by cross-wise ribbing. The round take-off port is coaxial in the standard version.
The standard round take-off port is male; the TRL2 version is available on request with male connector fitted with gaskets.
Available materials — Product code examples
TRT-…- GS -…-… — galvanized steel sheet
TRT-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
TRT-…- A -…-… — AW-1050A H24 aluminium sheet

The T-connectors allow building a T-connection between a round and a square duct. One end features a flange frame of sheet angles or a hemmed flange. The round duct ends are provided with hemming for sheet screws in the standard version.
T-connectors can be fabricated as a fully round T-pieces on request.
Available materials — Product code examples
T-RTR-…- GS -…-… — galvanized steel sheet
T-RTR-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
T-RTR-…- A -…-… — AW-1050A H24 aluminium sheet

The four-way piece ends are fitted with sheet angles, and the entire fitting is braced by cross-wise ribbing. This fitting allows building ductwork with branches taken off at 90 degrees.
Available materials — Product code examples
FW-ST-…- GS -…-… — galvanized steel sheet
FW-ST-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
FW-ST-…- A -…-… — AW-1050A H24 aluminium sheet

All four-way pieces with round take-offs are fitted with flange frames made of sheet angles and braced by cross-wise ribbing. The round take-off ports are coaxial in the standard version. The standard round take-off ports are male; the CZL2 version is available on request with male connectors fitted with gaskets.
Available materials — Product code examples
FW-RT-…- GS -…-… — galvanized steel sheet
FW-RT-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
FW-RT-…- A -…-… — AW-1050A H24 aluminium sheet

The wye tees are fitted with sheet angles, and the entire fitting is braced by cross-wise ribbing. This fitting allows building the ductwork with two take-offs set at any angle. The width may vary between the two take-off ports. Vanes can be installed

Available materials — Product code examples
S1-…- GS -…-… — galvanized steel sheet
S1-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
S1-…- A -…-… — AW-1050A H24 aluminium sheet

The wye tee (pant) are fitted with sheet angles, and the entire fitting is braced by cross-wise ribbing. The wye te divides the air flow between two parallel legs.
Available materials — Product code examples
S 2-…- GS -…-… — galvanized steel sheet
S 2-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
S 2-…- A -…-… — AW-1050A H24 aluminium sheet

All T-pieces with take-off bends are fitted with flange frames made of sheet angles and braced by cross-wise ribbing. A take-off bend provides smooth distribution of air without increasing the flow turbulence due to the presence of a vane.
Available materials — Product code examples
SBT-…- GS -…-… — galvanized steel sheet
SBT-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
SBT-…- A -…-… — AW-1050A H24 aluminium sheet

The 90˚ elbows are fitted with sheet angles, and the entire product is braced by cross-wise ribbing. The elbows are recommended for low air velocity and/or low-pressure ventilation systems and smaller sizes of side b ≤ 400 mm. The standard radius is r = 120 mm.
Typical applications of the elbows include rerouting the ductwork by 90 degrees with the same clear cross-section

 The 90˚ elbows are fitted with sheet angles, and the entire product is braced by cross-wise ribbing. The elbows are recommended for low air velocity and/or low-pressure ventilation systems and smaller sizes of side b ≤ 400 mm. The standard radius is r = 120 mm.
Typical applications of the elbows include rerouting the ductwork by 90 degrees with the inner clearance varying along the elbow path.
Available materials — Product code examples
VRE-…- GS -…-… — galvanized steel sheet
VRE-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
VRE-…- A -…-… — AW-1050A H24 aluminium sheet

The standard 90˚ bends are fitted with sheet angles, have an inner and outer rounding, and the entire product is braced by cross-wise ribbing. The bends are recommended for high air velocity and/or higher pressure ventilation systems and greater sizes of side b > 400 mm. The standard radius is r = 120 mm.
The standard angle is a= 90˚. Typical applications of the bends include rerouting the ductwork by 90˚ with the same clear cross-section.
Available materials — Product code examples
RBE-…- GS -…-… — galvanized steel sheet
RBE-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
RBE-…- A -…-… — AW-1050A H24 aluminium sheet

The standard 90˚ bends are fitted with sheet angles, have an inner and outer rounding, and the entire product is braced by cross-wise ribbing. The bends are recommended for high air velocity and/or higher pressure ventilation systems and greater sizes of side b > 400 mm. The standard radius is r = 120 mm.
The standard angle is a = 90˚. Typical applications of the elbows include rerouting the ductwork by 90 degrees with the inner clearance varying along the elbow path.
Available materials — Product code examples
VRBE-…- GS -…-… — galvanized steel sheet
VRBE-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
VRBE-…- A -…-… — AW-1050A H24 aluminium sheet

The eccentric reducers are adapters designed for coupling two rectangular ducts of different sizes. The ends are fitted with sheet angles, and the entire fitting is braced by cross-wise ribbing. The eccentric reducers help route the ventilation ductwork with liberal modifications of all duct dimensions and offsetting the center line by any value in both directions.
Available materials — Product code examples
ER-…- GS -…-… — galvanized steel sheet
ER-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
ER-…- A -…-… — AW-1050A H24 aluminium sheet

The reducers are adapters designed for coupling two rectangular ducts of different sizes.
The ends are fitted with sheet angles, and the entire fitting is braced by cross-wise ribbing.
The reducers help in routing ductwork at points where a symmetric cross-section reduction is required. The ducts are kept coaxial at both ends.
Available materials — Product code examples
CR-…- GS -…-… — galvanized steel sheet
CR-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
CR-…- A -…-… — AW-1050A H24 aluminium sheet

This transition piece changes the ductwork shape from rectangular to round. The fitting helps route the ventilation ductwork with liberal modifications of all duct dimensions and off setting the centreline by any value in both directions. The round connector is male in the standard version. The PRL7 fittings have a male connector fitted with a gasket.
Available materials — Product code examples
ER-S/R-…- GS -…-… — galvanized steel sheet
ER-S/R-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
ER-S/R-…- A -…-… — AW-1050A H24 aluminium sheet

 This transition piece changes the ductwork shape from square to round. This fitting helps in routing round and rectangular ducts with the centerlines aligned. The square connector has a flange frame in the standard version. The round connector is male in the standard version. The PRL1 fittings have a male connector fitted with a gasket.
Available materials — Product code examples
CR-S/R-…- GS -…-… — galvanized steel sheet
CR-S/R-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
CR-S/R-…- A -…-… — AW-1050A H24 aluminium sheet

The T-piece ends are fitted with sheet angles, and the entire fitting is braced by cross-wise ribbing. The T-piece helps building ductwork with a take-off branch at 90 degrees, reduction of the main duct clear passage and an offset by any value of size m. The take-off can be fabricated with height other than that of the T-piece.
Available materials — Product code examples
CR-STO-…- GS -…-… — galvanized steel sheet
CR-STO-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
CR-STO-…- A -…-… — AW-1050A H24 aluminium sheet

The concentric reducing T-piece ends are fitted with sheet angles, and the entire fitting is braced by cross-wise ribbing. The round take-off connector is male and located symmetrically in the side wall. This fitting helps building ductwork with a round take-off at an angle; the angle value depends on the wall slope at the take-off side.
Available materials — Product code examples
CR-RTO-…- GS -…-… — galvanized steel sheet
CR-RTO-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
CR-RTO-…- A -…-… — AW-1050A H24 aluminium sheet

Offsets help bypassing obstacles along the ductwork route, e.g. at intersections of two ducts. The ends are fitted with sheet angles, and the entire fitting is braced by cross-wise ribbing.
To achieve the required air flow rate, appropriate length sizes l and offset sizes e should be used.
Available materials — Product code examples
OD-…- GS -…-… — galvanized steel sheet
OD-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
OD-…- A -…-… — AW-1050A H24 aluminium sheet

Variable diameter offsets facilitate bypassing obstacles along the ductwork route while changing the connected duct height, which helps building intersections of two ducts. The ends are fitted with sheet angles, and the entire fitting is braced by cross-wise ribbing. To achieve the required air flow rate, appropriate length sizes l and offset sizes e should be used.
Available materials — Product code examples

V-OD-…- GS -…-… — galvanized steel sheet
V-OD-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
V-OD-…- A -…-… — AW-1050A H24 aluminium sheet

The angle rectangular duct spigot plates are tipped with sheet angles at one end. The other end features a spigot plate similar to a roof kerb, the size of which can be chosen according to individual requirements. The duct angle to the plate can be anywhere between 10 and 90
degrees according to individual requirements.

Flexible duct connector for rectangular ducts and elements. It is made of PQ flange channel and NQ corners interconnected by AMT flexible connection. Rectangular flexible duct connectors can be used to join ventilation ducts but above all it is used to eliminate vibrations caused by air handling units and fans. The design of the AMT flexible duct connector (a joint consisting of a layer of fabric and two strips of sheet metal on both sides) ensures very good airtightness.
Available materials
FDC-…-…-… – galvanized steel sheet, PVC coated fabric
FDC- -HI-T-… – galvanised steel sheet, silicone coated fabric
FDC-PU-…-… – galvanised steel sheet, polyurethane
(PU) coated fabric
FDC- K-PU-… – stainless steel polyurethane (PU) coated
FDC- NEP -… – galvanised steel sheet, neoprene coated fabric

The end caps stops square duct ends. The product is made from galvanized steel sheet.
The flange is made of sheet angles.
Available materials — Product code examples

EC-…- GS -…-… — galvanized steel sheet
EC-…- SS -…-… — 1.4301/304 or 316L stainless steel sheet
EC-…- A -…-… — AW-1050A H24 aluminium sheet