Product Overview
Stainless-Steel Hand-Twist Water Plug – Model ZB1903 / “Hand Twist The Water Plug”
RICHWITS ZB1903 lets you open or seal the bilge with a simple quarter-turn—no tools, no lost keys, no stripped slots.
CNC-machined from marine-grade 316 stainless steel, molybdenum-stabilised for lifetime immunity to salt spray, brine and tropical humidity.
One-piece 5 mm thick forged body—20 % heavier than DIN 86261—handles high cantilever & impact loads without flex or fatigue.
Hand-wheel is laser-etched “OPEN/CLOSE” and knurled for wet-grip; internal O-ring (Viton®) gives 100 % watertight seal on hulls 5–25 mm thick.
Dimension & Weight
| CODE | Thread | A mm | B mm | C mm | D mm | E mm | F mm | Hex / Knurl | WT kg | Hull Range |
| ZB1903 | T22 (1"-14 UNS) | 51.0 | 37.0 | 40.0 | 25.5 | 5.0 | 5.0 | Hand-knurl 33 mm | 0.110 | 5–25 mm |
Key Features & Benefits
316 SS One-Piece Forging – zero weld seams, zero rust, zero failure.
Hand-Twist T22 Thread – quarter-turn open/close; no tools, no sealant.
5 mm Wall Thickness – survives grounding impact or trailer-roller knock.
Viton® O-Ring Captive – fuel, oil & UV proof −30 °C to 200 °C; replace in 10 s.
Deep 90° Saddle – keeps plug clear of walking surfaces; no tripping, no rattling.
Laser-Etched OPEN/CLOSE – visible even when covered in mud or sunscreen.
Lightweight 110 g – 40 % lighter than bronze equivalents—cuts shipping cost.
Usage Scenarios
Garboard / Transom Drain – primary bilge emptying on skiffs, RIBs, sailboats.
Live-Well / Fish-Box Drain – hand-twist to empty, reverse to seal—no lost brass keys.
Ice-Chest Outlet – salt-proof plug for built-in coolers.
Deck Drain Blank – temporary seal for scupper testing or winter lay-up.
Why Choose RICHWITS
Factory-Direct – wholesale & retail welcomed, 25 % cost saving vs. bronze equal.
In-Stock – 5 000 pcs ready, MOQ 100 pcs, 48 h dispatch.
Fast Logistics – FedEx/UPS/DHL global 3-7 day delivery.
OEM/ODM – custom thread, hand-wheel colour or logo within 10 days.
Test Certificates – mill cert, 1 000 h salt-spray, torque-seal report supplied free.
FAQ
Q1: Will 316 SS really never rust?
A1: Correct—2-3 % Mo gives lifetime immunity to chlorides; polish yearly to keep the mirror shine.
Q2: What hull thickness will it seal?
A2: T22 taper + captive Viton O-ring seals 5–25 mm thick hulls; longer shanks on request.
Q3: How many turns to seal?
A3: Quarter-turn (90°) from finger-tight to full seal; knurled wheel supplies 8 N·m.
Q4: Can I weld the flange after installation?
A4: Yes—316L composition allows TIG field welding; polish heat tint with included restore pad.
Q5: Are spare O-rings available?
A5: Yes—10-pack of Viton O-rings, MOQ 50 packs, $0.20 each.
Q6: Do you offer test certificates?
A6: Mill certificate for 316 SS, salt-spray report, and torque-seal certificate supplied free on request.
Packing & Delivery
Exihibition
