TimberTech Cortex Collated Vintage 2.5-in Gold Concealed Screw Hidden Fastener 100-sq ft (350-Pack) in the Hidden Deck Fasteners department at Lowes.com
Advanced PVC Cortex Hidden Deck Fasteners + Bit | TimberTech
Cortex FastenMaster Concealed Fastening System 50 lin ft with 2 Screws For Use With AZEK Traditional Trim : Amazon.co.uk: DIY & Tools