A brochure for helium probes in pdf format can be downloaded.

Each probe is made to customer order, and its part number describes all the required details.  There are six fields in the part number, which has the general form:

MR-TL-AL-CN-NN [option codes]

Each of these codes have a meaning as described here:  All dimensions are expressed in millimeters, except where stated.


Due to the change in nomenclature necessitated by product improvements, there are a few cases where a product code has had to change. The changes are summarised here. The examples given here are where a code has been used in the past, but to specify the same unit with the change, a part code has to be changed. Other possible codes which were never required to be specified before are not listed here.

    Former code
    New code
Glass fibre tubing for probe, original superconducting element Product code starts GF- Product code starts GS-
Tufnol tubing for helium probes Product code starts TF- Series withdrawn due to poor available tubing
PTFE/Teflon tubing for probe, original superconducting element Product code starts PF- Product code starts PS-
HDI with Serial port option (up to 1997) HDI-xS [O1]... HDI-x [O1]...
HDI calibrated for original superconducting element (from autumn 2002) HDI-x [O1]... HDI-xS [O1]...

Twickenham Scientific Instruments Ltd.  Registered in England No. 2991094
Registered Office:  61d St. Margaret's Road, Twickenham, Middlesex. TW1 2LL, UK.
Telephone: +44 20 8892 7400
Email: sales@twicksci.co.uk