Wilkins 3/4 in. NR3XL Pressure Reducing Valve Single Union Female x Female NPT Connection Lead Free 34-NR3XL - The Home Depot
Watts 3/4 in. Copper FPT x FPT Water Pressure Reducing Valve 3/4 LF25AUB-Z3 - The Home Depot
Pressure Reducing Valves
Push Fit Tee Stop Valve - 1/2" Push x 1/2" Push x 1/4" Compression Water Shut Off Valve,1/4 Turn Chrome Water Line Splitter for Cooper, PEX,PVC Pipe, Tubing - Amazon.com
Plastic Pressure Relief Valves - MGA Controls
UPVC safety valve Back pressure valve PVC plastic pressure relief valve Safety relief valve 32mm DN25 1 inch - AliExpress