Oil marks for compressors

Sight glass oil indicator with lens for compressors with a male thread

A reliable oil sight glass is the absolute basis for safe operation of every oil-lubricated compressor. Our replacement oil sight glasses stand out thanks to their innovative shape and a highly resistant material that guarantees you a trouble-free overview of the lubricant level.

✅ Perfect visibility: The special magnifying-lens shape greatly improves the reading of the level, even when viewed from the side.
✅ Durable material: Made of transparent polyamide-based technopolymer (PA-T), which guarantees a long service life and mechanical resistance.
✅ Guaranteed tightness: By observing the prescribed tightening torque (see table) you achieve optimal tightness and the correct position of the sealing ring with no risk of oil leakage.
🔹 Important maintenance note: The material must not come into contact with alcohol or alcohol-based cleaning agents, otherwise it may become cloudy or damaged.

Replacement oil sight glass for compressors with a male pipe thread
Order number	Thread "	Dimensions mm					Tightening torque Nm	Weight g
Order number	Thread "	A	B	D	d	s	Tightening torque Nm	Weight g
13651	G1/4"	10	6	18	9	15	2-3	3 g
13671	G3/8"	7,5	7	22	11	19	3-5	4 g
13691	G1/2"	10,5	8	26	14	22	4-6	5 g
13721	G3/4"	10,5	9	31,5	20	27	6-8	8 g
13741	G1"	11	10	40	25	34	8-10	12 g
13761	G1 1/4"	11,5	13	47	30	40,5	8-10	20 g

Ventilek advises: Do you know that unpleasant feeling when you are trying to find out whether your compressor has enough oil and you cannot see a thing through the old, clouded glass? These new oil sight glasses with a magnifying-lens effect are an absolute lifesaver! You can read the level nicely even from a sharp angle, so you do not have to do gymnastics around the machine. But I have two important requests from practice – first, fit it with care, following the torque values in the table. As soon as you crank it down by brute force, the plastic can crack. And second, remember that when cleaning the outside, this material does not tolerate alcohol, otherwise the polyamide will go cloudy right away!