Back-Up Ring

Enhance the performance of your heavy equipment with the Case Construction Back-Up Ring #155120A1. Designed for durability and reliability, this essential part ensures optimal sealing and efficiency in hydraulic systems, keeping your machinery running smoothly.

Compatible equipment

This part fits CASE CRAWLER EXCAVATOR, CRAWLER EXCAVATOR TIER 3 (NA), LONG CARRIAGE - CRAWLER EXCAVATOR - TIER 4B (NA), CRAWLER EXCAVATOR TIER 4 (NA), CASE CRAWLER EXCAVATOR (NORTH AMERICA), CASE CRAWLER EXCAVATOR (EUROPE) including models 9040, CX240B, CX240BLR, CX290B, CX290D LC MH, CX300C, CX300D LC, CX330, CX350, CX350B.

Frequently asked questions

What is the part number?

The manufacturer part number is 155120A1.

Is this a genuine OEM part?

Yes. Southeastern Equipment stocks OEM and quality aftermarket parts for heavy equipment. Contact us if you need a specific OEM source or aftermarket option.

Will this fit my machine?

See the compatible equipment list above. If your model is not listed, call us with your machine's serial number and we can confirm.

Where does this ship from?

Southeastern Equipment Company ships parts nationwide from our US warehouse. Orders placed before 2 PM ET typically ship same day.

Ships nationwide. In-stock parts ordered before 2:30 PM ET ship the same business day. Your exact shipping cost and delivery estimate are calculated at checkout from your ZIP code and the part’s size and weight; oversized and truck-freight items may need extra transit time and freight charges.

Free branch pickup is also available across Ohio, Indiana, Michigan, and Kentucky — just choose it at checkout.

30-day returns. New, unused parts in original packaging may be returned within 30 days. Some items — including electrical, special-order, and direct-from-supplier parts — are non-returnable. See our full return policy.