NEW D1PRO TACTICAL & ESCAPE Models- EN341 Approved

February 26th 2021

The D1 Descender is the fourth in the range of D-Series specialist Descenders.  The D1PRO Descender utilises our patented D-Series progressive cam technology and specifically designed ø6mm (1/4") rope, to achieve genuine one-handed descent control, with performance characteristics comparable with those of an ø11mm (7/16") rope Descender device!

The D1PRO Descender is a compact, lightweight device, which can be stored in the user's harness and efficiently deployed, as required.  The D1PRO Descender is an auto-stop device (descent ceases when the user releases the control handle).  The absence of a panic brake on this 'PRO' model, allows the user the freedom to descend, without accidental activation of the panic brake.   This can be useful on longer, faster descents and in emergency situations when an efficient, uninterrupted descent is particularly important.

D1PRO ESCAPE (KT851) and D1PRO TACTICAL (KT850) Descender Kits have a rated load of 140kg (308lbs) and are certified to EN341-D*.  [We also offer a non-Certified D1PRO TACTICAL+ (KT852), which has an increased rated load of 175kg (385lbs)].


The D1PRO TACTICAL (KT850) Model is designed for professional users, in specialist applications.The D1PRO TACTICAL Descender is fitted with a high friction spur which allows the user to transition between standard and high-friction mode, as required.  The  D1PRO TACTICAL Descender model is fitted with a latch which can be disengaged, to allow the plate of the Descender to swing open.  This means that the device is mid-line attach/detachable, without the need for the user to disconnect the device from their harness.

The D1PRO ESCAPE (KT851) has design features which are suited to emergency escape/egress applications.   The D1PRO ESCAPE has a single friction mode (the high friction spur is omitted from the ESCAPE model), in order to provide a Descender which is simple to use, yet still offers genuine one-handed operation, up to maximum load. The D1PRO ESCAPE Descender has additional safety features built in.  The Descender has an anti-tamper closure and locking screw. This means that the rope cannot be accidentally removed from the device and re-installed incorrectly.  This gives further peace of mind that the device is ready to use in an emergency situation.


D1PRO Descender Kits are available with three mid-line attachable components, which can be easily configured in order to transition between descent, ascent and hauling. The D1PRO Accessories offer a versatile, super-compact and lightweight rescue solution to users, who can carry the kit on their harness, ready to be quickly and efficiently deployed as required. 

A1 Ascender & C1 Combination Pulley

The A1 Ascender is an extremely compact, mid-line attachable device.  The  squeeze-style cam, allows for smooth, ergonomic adjustment.  The attachment hole of the A1 Ascender accepts a Karabiner Connection (for use as part of a hauling/ascent system).  Alternatively, the C1 Combination Pulley can be clipped directly in to the attachment hole of the A1 Ascender (without the need for a Karabiner/connector).  

The C1 Combination Pulley has an attachment bollard (rather than an attachment hole) and a swing-cheek which is fitted with a spring-loaded closure mechanism.  The profile of the bollard also allows for Karabiner connection.  The attachment bollard profile features a central groove which is designed to centralise the Karabiner connector, keeping the pulley system balanced.  The Pulley is fitted with a super lightweight Acetal wheel.
Micro Accessory Pulley
The Micro Accessory Pulley is an extremely compact (53 x 31mm /  2 1/16 x 1 1/4") pulley with a strength rating of 25kN (5620lbf). The Micro Accessory Pulley has  swing-cheeks, with an Acetal wheel and an attachment hole which is suitable for a standard Karabiner connection.
Rope Options
Our design team took an holistic approach to the design of the D1PRO Descender kit and developed the descender cam in unison with two specifically designed ropes:
ISC QUADRA rope has a unique four-strand Nylon core, which is protected by a highly heat resistant Technora Sheath.  Technora decomposes at 498°c (930°F), with a Nylon core which is resistant to melting, up to 215-221°c (419-430°F).  The Quad-core construction of this unique rope provides perfect support to the device cam and optimally balanced firm, yet flexible, performance, with twist minimising qualities.  ISC QUADRA rope offers superior performance and handling of the D1PRO Descender and accessories.
ISC ESCAPE6 is a full Technora Rope, with ultimate heat-resistant properties. Technora decomposes at 498°c (930°F) and therefore ISC ESCAPE6 should be chosen for applications where there is the risk of extreme heat (burning structures, etc).
D1PRO Kits are suitable for use with ø6mm ISC QUADRA or ISC ESCAPE6 Rope, ONLY.
D1PRO Descender- Patented GB2522179 (further Patent Pending)
A1 Ascender & Accessory Pulley- Patents Pending
* CE EN341 Certification applies to the D1PRO Descender (KT850 & KT851 models), when used with ISC QUADRA or ISC ESCAPE6 rope, ONLY.

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Printed from on 31/05/2024 00:02:11.

International Safety Components Ltd., Unit 1, Plot 2, Llandygai Industrial Estate, Bangor, Gwynedd, LL57 4YH, United Kingdom

Tel: +44 (0) 1248 363 110
Email: [email protected]