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CSL428SP

Imperial Structural Locking Crownserts

CSL Series / Locking Type / SP / Structural

Installed using the Crownserts Hand-Installation Tool:  CSTL428

CSL428SP CS Series is a locking imperial Crownserts® threaded insert for durable thread reinforcement. silver-plated 17-4PH stainless steel; specified with 1/4-28 UNF internal thread and 5/16-24 UNF installation thread.

Crownserts can offer you the part CSL428SP with Certificate of Quality, Certificate of Conformity and Certificate of Origin on request.

Thread & Dimensions

A internal thread (Class 3B) 1/4-28 UNF
B external thread (Class 3A) 5/16-24 UNF
Ø max minor special .2785
Ø C (+.008/-.002) .252
D (+.015/-.000) .095
E .210
G (±.010) .380
J (±1) 24
Through-hole preparation Min. full THD depth .519; Min. full depth .415
Blind-hole preparation Min. full THD depth .519; Min. full depth .415
CSL428SP schematic

Material & Finish

Material 17-4PH, Cond H1025 per AMS 5643
Finish PASSIVATED per AMS 2700 & Silver Plated per AMS 2411 (.0002 min. thickness)
Temperature range -110°/+900°F
Heat treat RC 35-42
Magnetic YES

Tooling & Preparation

Hand-installation tool part number CSTL428
Step drill part number CSD0281
Tap through tool part number TTI0312
Blind tap tool part number TBI0312
Removal tool part number CSRT428

Crownserts is offering part CSL428SP as factory new.