The Chapin Shut-off Assembly - Poly With Gauge (6-8175) is a replacement part for the Chapin Tree/Turf Pro BackPack Sprayer (#62000). It cannot be used with any other sprayers as far as we are aware. The replacement shut off for the Chapin 4 Gallon 20V 63985 is the 6-8138.
The Chapin Shut-off Assembly - Poly With Gauge will fit the model 61800.
The Chapin Shut-off Assembly - Poly With Gauge (6-8175) is a replacement part for use with Chapin Tree/Turf Pro BackPack Sprayer (#62000) only.
All Chapin parts will work for the compatible Chapin sprayers. We recommend consulting with the sprayer manufacturer for more information on part compatibility for your unit.