Home > Companies > Invisible Connections Ltd > RVK Stair Connectors

The Invisible Connections range of telescopic connectors was developed to solve the problem of unsightly support systems for precast slabs and beams (e.g. traditional bracketry and/ or corbel support details). They consist of a cast-in, structural steel hollow section with inner structural steel hollow section deployed during installation. The position of the inner tube of the RVK unit is adjusted through a slot in the surface of the staircase element. The units have a safety stop at the back of the inner tube to prevent overextension. The range of RVK connectors are primarily intended for precast stairs and landings, with a standard capacity of 100 kN. They are also useful for conditions other than stairs.


  • No bolts required.
  • Recess in wall provides ample tolerance.
  • No traditional angle supports means no crane.
  • Recesses are formed between wall reinforcement.
  • Tolerance gap required only 20 mm between landing and wall.
  • No tools required.
  • No obstructions means a clear route for following trades.
  • All operations are safely conducted from above landing.
  • Connectors automatically fireproofed after grouting.
  • Connectors are concealed from view.
  • Handles any shape concrete element.

Related literature

The following content references this product:

Standard product features

Dimensions (w x h x t):

  • Outer tube: 120 x 60 x 4 mm.
  • Inner tube: 100 x 50 x 6 mm.


Steel (grade S355, minimum).

Concrete strength class (minimum):


Reaction to fire:

Class A1, according to EN 13501-1.


Product reference:

  • RVK 101-30 (pinned version) provides an axial tie into the wall, satisfying robustness requirements where only two walls are available for connection, if this cannot be achieved using the standard RVK 101 in an orthogonal layout.
  • RVK 101-30-E20 (extended version) spans the large air gap between landing and wall whilst maintaining secure embedment (in wall).

NBS Specification

NBS Create logo
This product is associated with the following NBS Create clause:
45-75-42/390 Carbon steel shear load connector

Product specification

An important note about specifying



Invisible Connections Ltd


+44 (0)1844 266000

Product reference

[RVK 101]
100 kN capacity.
[RVK 101-30]
See options.
[RVK 101-30-E20]
See options.

Steel finish

[Hot dipped galvanized]

Manufacturer details

Unit 6 Thame Forty,
Jane Morbey Road,
Oxfordshire, OX9 3RR
Tel +44 (0)1844 266000
Fax +44 (0)1844 390167
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