The PJ12126TW is the twist latch version of the 12 x 12 x 6 PJ Series window enclosure. It is a Type 4X fiberglass polyester box with a hinged cover and polycarbonate window, used as an instrument enclosure, electrical junction box, terminal wiring enclosure or control housing where the internals should be visible.

The drawing specifies 316 stainless steel lockable twist latch hardware, a 316 stainless steel hinge and a FIP polyurethane gasket. Box and cover are compression molded fiberglass reinforced polyester in gray, protected by enhanced UV inhibitors, with a 0.13 in (3.30 mm) wall. The series notes the door fasteners include a provision for padlocking.

Dimensions in the ordering table are 12.13 in H x 12.13 in W x 6.13 in D (308 x 308 x 156 mm), while the part page reads 12.32 x 12.32 x 6 in (313 x 313 x 152 mm). The enclosure ships at 8 lbs (3.63 kg). The optional 14R1111 inner panel is 10.75 x 10.88 in, and the drawing lists back panels in 0.100 in aluminum, 0.075 in white steel and 0.125 in fiberglass.

Four 316 stainless steel feet attach to #10-32 brass inserts at the rear. Series standards are UL 508A Type 1, 2, 3, 4, 4X, 12 and 13, cUL per CSA 22.2 No. 94 and IEC 60529 IP66. PJ12126TW is RoHS and REACH compliant.