Your search for "Water flow parts" revealed the following:

Riveted Sill Header Set: Echo Model Unpainted Kit HO (1:80) 1695

Code Outer diameter approx. 1.2 mm Black colour : Sakatsu Material Non-scale 4517

Constant current diodes (approx. 6mA) 3 pieces : Sakatsu Material Non-scale 2906

Spongebob Material [Flowering Forage] Yellow Flower (Yellow) : Woodland Material Non-scale F176

Constant current diodes (approx. 10mA) 3 pieces : Sakatsu Material Non-scale 2907

TMD-521 General-Purpose Bus Number Decal A: Tokyo Modeling Expression Water-Slide Decal N (1:150)

Woodland lighting system special lighting LED and light hub set JP5700 : Woodland electronic parts Just Plug compatible

Expansion hub for Woodland lighting system JP5702 : Woodland electronic parts for Just Plug

Outdoor water heater: YSK unpainted kit N (1:150) Part no. 222

Light hub for Woodland lighting system JP5701 : Woodland electronic parts for Just Plug

Grass sheet Realistic wild grass [Spring meadow] : Heki material Non-scale 1841

Power adapter for Woodland lighting system JP5770: Woodland electronic parts for Just Plug

Winter fields, the season of migratory birds : Miniatures Nature Materials Non-scale 765-24

Constant Current Diodes (around 15mA) 3pcs : Sakatsuo Electronic Components Non-scale 2908

Townscape Accessories : Farrar Unpainted Kit HO (1:87) 180585

Semi-circle 2.4 x 4.8 x 250 mm: Plastruct plastic material, non-scale 90886

12V to 5V Conversion Adapter: Sakatau Electronic Components 2565

Code Outer diameter approx. 0.8 mm Black colour : Sakatsu Material Non-scale 4515

Code 70 rail 3 ft (90 cm): Micro engineering material 16-070

Tunnel liner, underground open-cut type, pack of 2: Molin material N (1:150) TL-51