1362715 Oil filter for I.C. engine J EBERLE 20 Sept 1971 43746/71 Heading B1D A screw-on oil filter for an I.C. engine comprises a casing 10 and a removable cover 21 which allows a clogged filter element 33 to be replaced therein. Casing 10 has an integral spindle 13 whose free end screws on to an oilreceiving conduit of the engine, thereby clamping cover 21 to the casing 10. A non-return valve 32 in the form of a resilient washer separates inlet apertures 25 in the cover from the space outside element 33, but if the filter is vertically mounted then valve 32 may be omitted, its function being assumed by the lower end cap 38 of the element 33 engaging lip 31 but being raised slightly therefrom by the incoming oil. A by-pass valve comprising another washer 42 is incorporated in end cap 38 and engages round spindle 13 when closed. Element 33 comprises several layers of non- woven rayon wrapped round a pleated inner perforate support tube, enclosed by a cylindrical outer perforate support tube and end caps. Filtered oil enters spindle 13 at inlets 17. After replacing a filter element, friction pads 46, 47 on the casing and cover hold them together while the filter is screwed on to the engine.