Please not piucture above is not correct, this quartz has the plain open end ( not flared)
Oase Replacement  Quartz Sleeve for the Oase range of filters and UVC's.
Oase Part Number 13325
Dimensions.
diameter 44 mm x 298 mm long with plain top rim (test tube style one open end)

This is a genuine Oase Replacement Bitron Quartz Sleeve for the Oase range Bitron UVC's.

The Oase Quartz Sleeve is suitable for the following Oase Products:

• Oase Bitron 18C pre 2015
• Oase Bitron 24C pre 2015