The nylon Niemoller webbing was first produced in 1981 (source: http://iacmc.forumotion.com/t10324-niemoller-webbing-variant-background-history#7527), with this particular harness being the first Niemoller product, by a private company operated by Johann Niemoller, a former Recce commando. The Niemoller line of webbing was intended to be sterile for external operations, with no components that can be traced back to South Africa; there are rumors that it was intended to be destroyed after use, though that is likely untrue given how modified and repaired examples have been found, such as Sample 2 on this page. Nearly all Niemoller webbing items were made from a 420D nylon packcloth material similar to the ones used in US ALICE packs. Webbing made from similar material derived from the original designs are still used today by the modern SANDF Recces.
Sample 1:
Medium size. Front straps cut to adjust size by a previous owner.
Swedish “Fixlock” buckles like hot extraction vest.

This key was found in the front right (as worn) zipper pocket.

Sample 2:
Used by 4 Recce operator (according to seller). 4 Reconnaisance Regiment is still active today and is South Africa’s martime special forces organization. For specific information about their later Border War era operations, see Iron Fist from the Sea: South Africa’s Seaborne Raiders 1978-1988 or Iron Fist from the Sea: Top Secret Seaborne Recce Operations (1978-1988) (same book).

A short length of synthetic cord was found in the small waist pocket on the left (as worn).

Has drain holes cut in the bottom, necessary for waterborne operations.

The buttpack in the back is long and narrow unlike Sample 1 which seems to be more conventional. This, along with the drain holes, indicates it was heavily modified by the user and/or a unit rigger.

Sample 2 on 1st Pattern Recce Jacket:

Comparison of Samples 1 and 2:
Sample 2 on top, 1 below. Sample 2 on left, 1 on right Sample 2 on left, 1 on right Sample 2 on top, 1 below.
Usage Photos:
SADF Recces:
5 Recce in 1987 meeting Koevoet (source: https://theafricancriminologyjournal.wordpress.com/2018/03/15/apartheid-south-africa-ops-k-koevoet/) 5 Recce

Executive Outcomes (1989 -1998):
Contractor on the far right, standing, is wearing a later version of this vest with ladder buckles, not fixlock like above samples.
More information about Executive Outcomes: https://www.globalsecurity.org/military/world/para/executive-outcomes.htm
SANDF Recces (after 1994):

US Troops in 1st Gulf War (1991):
This was likely the commercial nutria version:

32 Battalion Version is an “expansion” of this design.