Chamsuri-class patrol boat

"Chamsuri"-class patrol vessels (Hangul: 참수리급 고속정) are naval boats that function as patrol boats. These entered service with the Republic of Korea Navy in the 1970s, and have since seen service with three other navies, of which the Philippine Navy is currently the largest import user.
These boats were built by the Hanjin Industrial SB, Chinhae, and Korea SB & Eng. Masan shipyards.
These boats, also referred to as patrol killer medium "PKM", were built in two batches: the 201 series, and the more heavily armed 301 series. Early PKM 201 series boats were initially armed with one 40 mm/60 Bofors Mk.3, one twin 30 mm/75 Emerlec EX-30, and two 20 mm/70 Mk.10 AA. Late PKM 201 boats were armed with one twin 30 mm/75 Emerlec EX-30, one or two turreted single 20 mm Vulcan Gatlings, and two single 12.7 mm machine guns. The PKM 301 boats were armed with one 40 mm/60 Bofors in a fully enclosed mount, two turreted single 20 mm Vulcan Gatlings, and two single 12.7 mm machine guns (before the Second Battle of Yeonpyeong two single 7.62 mm M60 machine guns). 
The "Chamsuri"-class boats are being retired and replaced by in the Republic of Korea Navy.
In Bangladeshi service.
The Bangladesh Navy operates four PKMs. The first two (P1011 and P1012) were transferred from South Korea in 2000. Another two (P1013 & P1014) entered service in 2004.
In Timorese service.
One naval and two coast guard units were transferred by South Korea to the Naval Component of East Timor's F-FDTL in September 2011, apparently on the basis of a transfer agreement signed in Seoul the previous month. 
They have been rechristened "Kamenassa", "Dili" and "Hera", respectively. Sub-class and original pennant numbers are currently unknown.
In Ghanaian service.
One vessel was transferred in 2011.
In Kazakh service.
Kazakhstan received three PKMs in 2006. These were purchased for a token amount of $100 per ship.
In Philippine service.
At least eight PKMs were transferred to the Philippines. The first five, PKM 225, 226, 229, 231, and 235, were transferred in 1995. Four were commissioned the following year, with one (ex-PKM 235) cannibalized for spare parts. Another unit was transferred in 1998. An additional two ships, PKM 223 and PKM 232, were acquired in 2006.
PKMs in Philippine Navy service are collectively referred to as the , named after Filipino officers and soldiers who served with distinction during the Korean War. These are listed below: