1/2" BSP Female Straight Barb Hose Connector – Plastic, 4–20mm

Match the barb diameter to your hose's inner diameter (ID). For example, a 4mm barb fits a hose with a 4mm ID (approximately 5/32"). Measure the inside of your hose before ordering. When in doubt, size down slightly — a snug barb creates a better seal than a loose one. Common conversions: 6mm ≈ 1/4", 8mm ≈ 5/16", 10mm ≈ 3/8", 12mm ≈ 1/2", 16mm ≈ 5/8", 20mm ≈ 3/4".

These connectors use 1/2" BSP (British Standard Pipe) female thread. BSP is a widely used standard in plumbing and fluid systems, particularly outside the US. It is not directly compatible with NPT (National Pipe Thread) fittings — the thread angles and pitches differ. A BSP-to-NPT adapter is required if connecting to NPT male ports.

The plastic body is generally moisture-resistant and suitable for aquarium, irrigation, and low-pressure water applications. Prolonged UV exposure or temperatures above typical ambient ranges may degrade the material over time. For harsh outdoor environments or high-temperature applications, a metal barb fitting is typically a better choice.

Plastic barb fittings of this type are generally rated for low-pressure applications — typically up to 30–60 PSI depending on fluid type and temperature. They are well-suited for aquarium air pumps, gravity-fed water lines, and low-pressure fuel systems. If your application exceeds this range, please contact us to confirm suitability before ordering.

These plastic connectors are generally suitable for light fuel applications such as small engines or gravity-fed fuel systems. Compatibility depends on the specific fuel type and concentration. For gasoline, diesel, or chemical-heavy fluids, verify material compatibility before use. For demanding fuel applications, a fuel-rated nylon or brass fitting is typically recommended.

For low-pressure applications such as aquarium air lines, a hose clamp is generally not required — the barb's ribbed profile creates a secure friction fit. For higher-pressure or vibration-prone applications (fuel lines, pressurized water systems), using a hose clamp is strongly recommended to prevent hose blowoff.

Common conversions for this product range: 4mm ≈ 5/32", 6mm ≈ 1/4", 8mm ≈ 5/16", 10mm ≈ 3/8", 12mm ≈ 1/2", 14mm ≈ 9/16", 16mm ≈ 5/8", 20mm ≈ 3/4". Always verify against your hose's actual inner diameter for the best fit and seal.