Grex A160000 - Pre-set adjustment knob Grex from $12.26 $14.95 Qty. Add to Cart SKU: GRX-A160000 This item is currently on backorder but you can still purchase it now and we'll ship as soon as more become available. Genuine Grex replacement part A160000 - Pre-set adjustment knob. For Grex Models TG, TS. Chart referance number 17. Tweet