Lockable 4 inch Oil Tank Inspection Cap

£29.17 ex VAT£35.00 inc VAT



Product Overview

Manufactured from an oil resistant polymer, this 4” Lockable Oil Tank Inspection Cap is suitable for retrofit to any Harlequin fuel tank incorporating an existing 4” Inspection Aperture and Screw Cap.

Designed to accept a combination or key activated padlock – readily available from almost any DIY or hardware store – when fitted, this product provides a visible and useful deterrent against fuel theft at installations incorporating a BioDiesel, Diesel or Heating Oil Storage Tank.

Standard Equipment

4” dia Oil Tank Inspection Cap with Locking Point
2 x Lockable Catch
4 x Self Tapping Screws


Suitable for any Harlequin tank produced since Summer 1997 and incorporating a 4” Inspection Cap. Please note that this product is supplied as standard on the following Harlequin tank ranges:
Harlequin HQI Bunded Heating Oil Tanks
Harlequin ITE Bunded Heating Oil Tanks
Harlequin Bunded Fuel Point and Fuel Station Diesel Fuel Tanks
Additionally, this product may be suitable for use with oil tanks supplied by other manufacturers. Please confirm with manufacturer prior to order placement.


  • Easy and quick to fit – no specialist tools required
  • Easy to use
  • Visible deterrent
  • Accepts both key and combination padlocks
  • Affordable

Please contact us for return details within 14 days of receiving your item. Returns should be unused, and suitable for resale.

Free UK delivery by Royal Mail. Please allow up to 5 working days for delivery.