Osram SubstiTUBE LED Tube Light 1200mm T8 18W

The Osram SubstiTUBE ST8E-1.2M is an 18W LED retrofit tube for 1200mm (4ft) T8 fittings, built to replace a 36W T8 fluorescent tube on an existing conventional (magnetic) ballast. It's aimed at offices, warehouses, and retail spaces moving from fluorescent to LED without rewiring the fixture.

Do I need an electrician for this?

No, if your fitting runs on a magnetic ballast: switch off the power, remove the old fluorescent tube, swap the fluorescent glow starter for the LED starter supplied with this tube, and fit the new tube — no rewiring involved. If your fitting uses electronic control gear (ECG/HF ballast), this tube is not compatible as-is; the ballast has to be bypassed and the fitting wired directly to mains, which is a job for a qualified electrician.

Key Features

• 18W LED replacement for a 36W T8 fluorescent tube — roughly half the running wattage
• Fits standard 1200mm G13 T8 fittings on magnetic ballast (starter swap required)
• ~100 lm/W efficacy, no mercury, no UV emission
• Instant start, no flicker or hum
• Available in 830 Warm White, 840 Cool White, and 865 Daylight

Technical Specifications

Applications

• Offices and open-plan workspaces
• Warehouses and stockrooms
• Retail and commercial fit-outs upgrading from fluorescent

FAQ

• Will this work with my existing ballast?
  Only if it's a magnetic/conventional ballast — you'll need to replace the fluorescent starter with the LED starter supplied. On electronic (ECG/HF) ballasts, the fitting needs rewiring by an electrician; this tube won't run on ECG unmodified.
• How do the 830, 840, and 865 versions differ?
  Only in colour temperature — 830 is Warm White (3000K) for homes and hospitality, 840 is Cool White (4000K) for offices, and 865 is Daylight (6500K) for workshops and retail wanting a brighter, whiter look. Output and fitting are otherwise identical.
• Do I need to remove the old starter?
  Yes — the fluorescent glow starter must be replaced with the LED starter that ships with this tube. Skipping this step causes the tube to blink and can damage it.
• How much energy will I save versus the fluorescent tube it replaces?
  This 18W LED tube is designed to replace a 36W T8 fluorescent tube, roughly halving running wattage in the same fitting.