If you thought the ZigZag/Zillon 'Request for Inspection' notice (NOTE: THIS IS NOT A RECALL) issued by Petzl in late August 2021 would kill the sale of these mechanical devices, you can think again. On the contrary, sales enquiries are as strong as ever, and most 'new to the ZigZag' climbers are disappointed to learn, they will have to wait until 2022 before they can enjoy the benefits of this device.
The original slippage issues covered in the Petzl Request for Inspection Notice appear isolated to a small number of units, judging by the number of NZ returns. The Petzl Inspection Notice covered ZigZag and Zillons with serial numbers between 18L 0000000 000 and 21G 0000000 000.
As far as Treetools is aware, the upgrades to the 2022 device are minimal, reflected in modifications to the top two links of the ZigZag/Zillon 'chain'. The spring tension and the surface treatment of the top links is the only apparent alteration - see link here, showing comparisons between the old and the new.
The 2018-21 ZigZag/Zillon models featured polished stainless steel chain links throughout the articulated chain, but the 2022 models have a brushed finish on the top two links, increasing the RA (roughness average) among other things. You are talking about the effects of nano friction here, which shows you how minor the variances on the ZigZag were in the first place. If you want more in-depth science regarding the relationship between surface roughness and friction you can read it here.
While the changes appear minimal, the rejigging of the manufacturing process does take time, hence the relatively long delay without the Petzl ZigZag/Zillon product in the market. Furthermore, New Zealand tree climbers can expect longer delays due to the Petzl supply chain via Australia. Roll on 2022.
Kiwi tree climbers, concerned about slippage on their Petzl ZigZag/Zillon, should follow the test procedure here. If your test results are not satisfactory, immediately stop using your Petzl ZigZag/Zillon and return the gear by contacting the Petzl New Zealand after-sales service centre via the contact form.