http://www.maib.gov.uk/cms_resources...s%20report.pdf

Recommendations
· Based on the results of this report it is recommended that yachtsmen
always
fit a radar reflector that offers the largest RCS practicable for their
vessel.
· The RCS of the radar reflector should have a minimum consistent RCS of
2m2.
· The Sea-Me is the recommended product if power is available
· If power is not available then the passive Large Tri-Lens reflector is
recommended
· The 4” tube reflector is not considered suitable due to its poor
performance. It
is also recommended that the 2” tube reflector is not suitable since the
performance of this target will be even lower.
· It is recommended that poorly performing radar reflectors are not
fitted as it
is possible that the user could be lulled into a false sense of security
believing
that their chances of detection has been enhanced.