Modular Supports System Product Technical Guide June 2026

Modular Support Systems Technical Guide, Edition 2

3.0 Modular Support System

3.2.2 MT Base Connectors

MT-B-O4

Description

4-hole base plate for back-to-back channel attachment to concrete or steel( X-BT / S-BT / F-BT compatible). Meant to be installed with a Twist Lock and Twist Lock Bolt.

Material Specifications

Standard 1 Grade 1 F y, ksi( MPa) F u, ksi( MPa)

GB / T 700 Q235 B 34.08( 235) 53.66( 370)

1 Mechanical properties of GB / T 700 Grade Q235 B meet or exceed the mechanical properties of ASTM A1011 SS Grade 33.

Corrosion Protection

Description	Environmental Conditions
MT-B-O4	Dry indoor conditions( C1) Indoor with temporary condensation( C2)
MT-B-O4 OC	Outdoor, low to moderate pollution( C3 / C4- low)

Ordering Information
Description	Weight Per Piece, lbs( kg)	Quantity Piece( s)	Item No.
MT-B-O4	7.28( 3.3)	4	2272098

MT-B-O4 OC 7.28( 3.3) 4 2272099

mm( in)

Figure 18 – MT Channel Anchoring to Concrete

Table 138- Allowable Strength Design( ASD) Load Data 1, 2, 3, 4

Fx lb( kN)	Fy lb( kN)	Fz lb( kN)	My lb ft( kN m)	Mz lb ft( kN m)
3,035( 13.50)	700( 3.12)	3,590( 15.98)	3,810( 5.17)	2,010( 2.73)
1 Minimum safety factor, Ω, for tabulated values is 2.0.
2 Multiply tabulated values by 1.5 to obtain minimum Load and Resistance Factor Design
( LRFD) values.
3 See Figure 18.
4 Load values are for base connector only. The design professional is responsible for
checking concrete and fastener strength.

Table 139- Limit State Design( LSD) Load Data 1, 2, 3

A. MT-40D, MT-50D, MT50 DU

Fx lb( kN)	Fy lb( kN)	Fz lb( kN)	My lb ft( kN m)	Mz lb ft( kN m)
4,095( 18.23)	945( 4.21)	4,665( 20.77)	5,015( 6.80)	2,645( 3.59)
1 Maximum resistance factor, φ, for tabulated values is 0.75.
2 See Figure 18.
3 Load values are for base connector only. The design professional is responsible for
checking concrete and fastener strength.

Modular Supports System Product Technical Guide June 2026 | Page 83