Is this compatible with flat mount frames?

No — the BR-MT520 caliper is post mount only. For flat mount frames (common on gravel bikes and some road bikes), you would need a flat mount caliper or an adapter.

Can I use DOT fluid instead of Shimano mineral oil?

No — DOT fluid will damage Shimano seals. Use only Shimano-specific mineral oil (SM-DB-OIL). This is clearly marked on the caliper body.

How do I bed in the new brake pads?

Perform 10-15 moderate speed stops from about 25-30 km/h without skidding. Avoid hard braking for the first 20-30 stops to allow the resin pads to transfer a layer onto the rotor surface.

Shimano

Shimano Deore BL-MT501/BR-MT520 Disc Brake and Lever - Rear, Hydraulic, Post Mount, Black

Name: Shimano Deore BL-MT501/BR-MT520 Disc Brake and Lever - Rear, Hydraulic, Post Mount, Black
Brand: Shimano
SKU: EMT501EJRRXMA170
Price: 8140.00 INR
Availability: InStock
Author: InstaSport Editorial

₹8140.00

Description

Shimano Deore BL-MT501 hydraulic disc brake offers reliable power and a rigid brake design for a multitude of riding styles, from XC to trail. Brakes are pre-bled Lever and calliper packaged separately The Deore BL-MT501 hydraulic disc brake lever contains a smooth and durable master cylinder design