As an owner of a 2012 Leisure Travel Sprinter conversion I have two of the refrigerator vents (identical top and bottom) on the left outside of the camper. The rear fixed fastener failed earlier and was replaced by a bent piece of thin aluminum strap. Then the latch slip up/down latch failed. This is my solution to avoiding trying to find a discontinued Dometic LS200 lower vent and doing the tare required out, paint and install of a new replacement vent. The failure was the latch button on the vent frame broke off of its mount. The seperation left the mount in place with a hole that had some plastic reminents form the now gone latch pin. The residual plastic was carefully removed and this piece was drawn to fit behind the hole and using something like JB-Weld to secure it in place. A 4mm screw was modified by putting a 4mm pan head screw in a hand drill and applying a file to remove portions of the screw head to have the size and shape of the latch pin. Then a nut was fitted in this repair part and solvent cemented in place while also attaching the top part which fits through the remaining hole in the old mount. The final result is a replacement latch pin that the sliding latch can lock onto. Printed in ABS (so it can be easily solvent cemented) and using two 4mm nuts one inside this part and one behind the part to lock the screw in place.