Complex sentence: These Vosper built boats are 103 foot Maybach Diesel powered built patrol crafts commissioned in the 1960s and armed with 2 x 40mm HA 70 Bofors guns mounted fore and aft with a design speed of 27 knots.
Split into simpler sentences: These Vosper built boats are 103 foot built patrol crafts commissioned in the 1960s. They were armed with 2 x 40mm HA 70 Bofors guns mounted fore and aft, powered by Maybach Diesel with a design speed of 27 knots.