Multi-Directionally Activated Sign Support Hardware

This ground mounted sign support system is a 4-inch square x 8 gauge steel tube with a superior Gatorshield finish to prevent corrosion. It’s designed to be impacted from any direction, and is field fit ready with the ability to hold up to 72 ft2 of sign area per post in a 90 mph wind zone.

The MASSH-400 has been successfully crash tested and meets the required MASH (Manual for Assessing Safety Hardware) Test Level 3 breakaway criteria and is eligible for reimbursement of funds on Federal-aid projects on the National Highway System.

The slip base and hinge have the strength to support a large sign area during normal conditions, yet allows the post to disengage from the stub with minimal force upon impact by an errant vehicle. The pivoting action of the hinge assembly aids in permitting the post to bend and/or pivot out of the way of the vehicle, allowing the vehicle to pass under the sign after impact.

The MASSH-400 will save time and money as well as provide a safer environment for everyone on the roadway before, during and after a traffic incident.

Truck Hits MASSH-400 Sign

Features and Benefits

Designed to be impacted from ANY Direction

  • The unique, patent pending Redi-Torque multi-directional triangular slip base is designed to be impacted from any direction and breakaway at impact, unlike typical beam posts.
  • Redi-Torque bolts can easily be installed in high impact areas, without the need for a torque wrench and still provide the necessary holding strength for the post they are supporting.
  • The Omni-directional hinge assembly for multiple posts assists the structure in moving out of the way of a vehicle caused by an impact and helps reduce damage to the sign panel and vehicle.
  • Done in accordance with AASHTO “Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals”, sixth edition.


Omni Directional Hinge Assembly

Omni Directional Hinge Assembly

Redi-Torque Slip Base System

Redi-Torque Slip Base System

Meets MASH TL-3, FHWA Eligibility Letter SS-180

The MASSH-400 has been crash tested by an accredited independent third-party facility and meets the required MASH Test Level 3 criteria in the AASHTO Manual for Assessing Safety Hardware.

Increased Safety

Simple product design, fewer parts and the ability to pre-cut posts reduces the installation time, which will minimize worker’s exposure to traffic. The MASSH-400 also offers vehicle protection with its Omni-directional hinge assembly allowing the vehicle to safely pass under the sign after impact.

Hold Large Sign Areas at Fairly High Sign Centroids

The MASSH-400 can handle up to 72 ft² of sign area at a 14 ft. sign centroid on a single post in a 90 mph wind zone and larger sign areas at higher sign centroids on multi-post installations.  The MASSH-400 has been approved to allow two posts in a 7 ft. span, and one can use 3, 4, or even 5 posts if the sign width allows. The system can hold substantially large signs, commonly mounted on W6x9, W6x12, W6x15, and in some cases even W8x18 beam posts.


Quick & Easy Installation

The MASSH-400 is not location specific. Once required lengths are determined, the square posts can be cut to length in the field and installed immediately. The simplicity of the product design allows for a quick and easy installation with fewer parts and fewer trips than other sign support systems.

With a stock of spare posts, hinges and hardware, reinstallation can be performed once a sign crew is available. This process will eliminate the need to wait for special fabrication. In most situations, the majority of the MASSH-400 components are undamaged after impact and can be reinstalled quickly with few replacement parts, which will minimize the need for temporary supports.

Material Savings

  • Replacement costs are reduced, as damaged posts are easily salvaged and cut in smaller useful lengths.
  • The hinge is designed to be rebuilt eliminating the need to purchase a new hinge assembly, which will lower Department of Transportation (DOT) maintenance costs.
  • The MASSH-400 requires fewer parts to stock, and can be used for virtually every installation.
Part NumberDescriptionWeight in Pounds
Contact us with required post lengths for their part numbers.
908856Complete MASSH-400 Redi-Torque slip base assembly for 4" square post, includes post receiver, Red-Torque match plate hardware and 36" Unibase78
913415Complete MASSH-400 Redi-Torque slip base assembly for 4" square post, includes post receiver, Red-Torque match plate hardware and 48" Unibase89
913416Complete MASSH-400 Redi-Torque slip base assembly for 4" square post, includes post receiver, Red-Torque match plate hardware and 54" Unibase95
90948813" Triangular slip base post receiver (top) for 4" SQ post25
90949513" Triangular Unibase slip plate w/anchor(stub) - 36"47
91341813" Triangular Unibase slip plate w/anchor(stub) - 48"58
91341913" Triangular Unibase slip plate w/anchor(stub) - 54"64
909496Hardware replacement set for post receiver/hinge
3 sets of 5/8" bolt, shoulder, nut & 4 each structural washers
9088603/4" Redi-Torque match plate hardware kit4.2
908857Complete hinge, assembled, for MASSH-400 post assembly23
909483Hinge repair kit, threaded stainless tube, 2 bolts, 2 washers1.6
909482Hinge Sleeve for X4-HINGE repair4.5
908859Universal post clamp for 4" square post with 2 stainless "T" head bolts (THBS38-200) & 2 nuts(CHFN38-Z)1.4
909506Universal post clamp for 4" square post with 2 stainless
rectangular head bolts (RHBS38-175) & 2 nuts(CHFN38-Z)
913420Sign Brace post clamp for 4" square post0.76
913421Extruded Panel post clamp for 4" square post0.51
908858Closure cap for 4" square post0.7

The MASSH-400 system is suitable for signs in many categories including: guide, logo, hospital, recreational, cultural interest and more!

  • Elevation can be measured and sign support system installed in one trip
  • Designed to deliver minimal damage upon impact to vehicle and installation
  • Hinge assembly is designed to be rebuilt saving time and money
  • Torque wrenches or other special tools are not required
  • All components are made, melted & coated in the USA
  • Increased worker and driver safety!

The MASSH-400 enhances the performance of large sign post systems as well as generate material and labor savings.

Choose the MASSH-400 today!

The MASSH-400 is manufactured by Allied Tube & Conduit in cooperation with Xcessories Squared.