POLICE are combing the territory for well-tonsured thieves who have posed as beauty salon customers to carry out a crop of hair salon robberies. Three salons in Wan Chai, Western Market and Wong Tai Sin were raided in the same week by robbers who first asked for either hair cuts, perms or manicures before escaping with thousands of dollars in cash and possessions. By posing as patrons, the thieves can look for gaps in the salons' security, and judge how well-off the customers are, said Mr Tsang Fu-luang of the Monea Beauty Parlour in Wan Chai. He said an identical technique was used several years ago during an earlier wave of hold-ups. ''It looks like the trend is coming back again,'' he said. ''My friend used to work in a salon in Yau Ma Tei, which is a crowded district. ''Three robbers came in and asked for perms. While having their hair done, they assessed the salon and its customers and tried to judge when the time was right. ''They could see if there was any security system in the premises or if there were any big men that might fight back,'' Mr Tsang said. On that occasion the robbers were able to make off with more than $10,000. ''The majority of the customers were club girls who wore some jewellery and carried a couple of thousand dollars each,'' Mr Tsang said. ''And my friend was robbed of his Rolex watch and a few thousand dollars in cash.'' Another hairdresser, who only wanted to be known as Mr Chan, said: ''My friend's salon was on the second floor. This was dangerous because no one could see when the robbers attacked.'' He said robbers usually attacked salons situated in secluded spots or those not on the ground floor. ''They also prefer the crowded ones because they have more customers to rob.'' But the Fight Crime Committee's Mr Justein Wong-chun said the number of hair salon hold-ups was insignificant, although he conceded that posing as a customer was a good way to study the salon. But he said no special effort would be made to look into these crimes by the committee. ''Customers and salons should take crime preventive measures,'' he said. Mr Andre Oullette from Andre Norman Haircutting Salon in Lan Kwai Fong, thought the whole thing was hair-brained. ''I've never heard of anything like that. It's crazy. But anything is possible,'' he said.