I don’t know, as I threw mine away. It broke during the second use. The pressure split the seam on the bottom, and my animal repellant sprayed all over from the bottom.

I need a replacement part .....used once and it will not hold pressure

Be sure NOT to OVERFILL liquids past the Water Line, always close the Gallon Container green cap securely before PUMPING HANDLE until it is quite resistent to use the SPRAY WAND to disperse spray water. ALSO, before ADDING or DRAINING any remaining water in the bottle, REMEMBER to RELEASE the pumped AIR remaining in the bottle by pulling the small funnel-shaped RED plastic piece near the GREEN cap of the bottle. Finally, ALWAYS DRAIN container AFTER use to not erode the plastic or clog the spray lines inside!

can I use this to spray stain on a deck?

I believe the STRAY NOZZLE, WAND & HOSE would become IRREPARABLY CLOGGED!!

Can I use this to spray bleach?

I imagine that you can use this equipment CONDITIONALLY to spray BLEACH, although I have not done so. Because the SPRAY WAND water line(s), connecting spray head with FINE SPRAY HOLES, as well as the gallon CONTAINER are substantially made of plastic/rubber, there may be resulting CLOGGING of those holes or DAMAGE to and/or CORRUPTION of those plastic parts. CAVEAT: DO NOT LEAVE OR STORE ANY BLEACH RESIDUE IN GALLON BOTTLE, and clear the SPRAY WAND LINES OR SPRAYHEAD(s). To minimize those potential damage issues, IMMEDIATELY after use, THOROUGHLY wash, rinse, re-spray with CLEAR WATER, then DRY to remove any Bleach residue after usage. Good luck!