# Through-hole tactile switch, 6 x 3.5 mm A 6 x 3.5 mm through-hole tactile switch (SPST-NO), APEM's MJTP1243 and MJTP1250. It has a black housing, a cover with a boss at each end, a rectangular actuator, and two bent terminals, one at each end. The body is centred on the origin, with its underside on the board's top face (the XY plane). The body's 6.0 length and the terminals lie along X: terminal 1 at -X, terminal 2 at +X. Its 3.5 depth lies along Y. `kind` is the MJTP number. | Type | Actuator's top above the board (L1) | Overall, tips to actuator (L) | |---|---|---| | MJTP1243 | 4.3 | 7.8 | | MJTP1250 | 5.0 | 8.5 | For both types: - The body is 6.0 long and 3.5 deep. Its top (the cover's) is 3.5 above the board, and the two end bosses stand 0.3 above that. - The actuator is 3.0 long (along X) and 1.5 deep (along Y). - The terminals are 1.0 wide and 0.3 thick. Their tips are 6.5 apart, centre to centre, and reach 3.5 below the board. - Each terminal runs down the housing's end, starts to bend out 0.7 below the board, is furthest out 1.8 below it (7.9 over both bends), and is straight again 2.8 below it. ## Source APEM, *MJTP Series 6mm Thru-Hole Mtg. Tact Switches*, catalogue section M, pages M3 to M7 (PDF created 2021-09-05, modified 2023-04-20), from the copy at mm.digikey.com (; APEM's own site isn't used). Dimensions are in inches (mm); the mm values are used here. - Page M6, MJTP1243 & MJTP1250 drawing: body .236 (6.0) long and .138 (3.5) deep; .138 (3.5) from the board to the cover's top; the end bosses .012 (0.3) above it; actuator .118 (3.0) long and .059 (1.5) deep; terminals .039 (1.0) wide and .012 (0.3) thick, tips .256 (6.5) apart and .138 (3.5) below the board; .311 (7.9) over the bends; the bend starts .028 (0.7), is furthest out .071 (1.8), and ends .110 (2.8) below the board. - Page M6, the table: MJTP1243 L1 .169 (4,3), L .307 (7,8); MJTP1250 L1 .197 (5,0), L .335 (8,5). - Page M3, Materials: case thermoplastic, black, UL94HB; actuator thermoplastic, black unless otherwise specified; cover/bracket PET film, tin plated brass or stainless steel; terminals silver plated brass. The sheet gives no weight. **Proportions, for looks only.** The drawing doesn't dimension the following. They are scaled from the drawing: - The cover, 0.3 thick, so the housing's top is 3.2 above the board. - The end bosses: 1.0 long (front view) and 2.0 deep (side view), at each end of the body, through notches in the cover. - The underside: four corner feet 0.4 high. The front view shows a recess 2.2 long in the middle, and the side view one 2.5 deep, so the feet are 1.9 x 0.5. - Where the terminals leave the housing: 0.8 above the board, on its end faces. Materials follow page M3: the housing and actuator black thermoplastic (`pa6`; the sheet names no resin), the cover PET film (`pet`, dark as in the sheet's photos; the sheet also lists tin plated brass or stainless steel for covers and brackets without saying which model has which), and the terminals brass (`brass`), silver coloured. The sheet's photos show one switch with a light actuator, but they aren't labelled, so both types are black as the materials say. **Mass check:** the sheet states no weight. As modelled, MJTP1243 is 0.071 g housing + 0.006 g actuator + 0.005 g cover + 0.024 g terminals = 0.11 g. ## Catalogue models The old `SW PUSH 1 P1 T 6x3.5mm H4.3 APEM MJTP1243` and `SW PUSH 1 P1 T 6x3.5mm H5.0 APEM MJTP1250` models name these exact parts, so they map to MJTP1243 and MJTP1250. They were measured on the reference models (2026-11-06). The terminals (pitch, width and thickness) and the body agree with the drawing; the other differences are below. | | Old models | APEM drawing | |---|---|---| | Body | 6.0 x 3.5, top 3.58 above the board | 6.0 x 3.5, top 3.5 | | End bosses | 0.8 x 2.0, about 0.3 high, tapered | 0.3 high (1.0 x 2.0 drawn) | | Actuator | 3.5 x 1.5 | 3.0 x 1.5 | | Actuator's top | 4.3 and 5.0 | 4.3 and 5.0 | | Terminals | 1.0 x 0.3, tips 6.5 apart, narrowed to 0.64 below 3.0 | 1.0 x 0.3, tips 6.5 apart | | Over the bends | 7.8, furthest out 1.8 below the board | 7.9, furthest out 1.8 below | | Tips below the board | 3.5 | 3.5 | | Underside | a recess 2.8 long across the whole depth, 0.4 high | four corner feet 0.4 high (proportion) | The family's other switches (DIP switches, slide and toggle switches, other makers' tactile switches) are other parts. See `COVERAGE.md`.